their having been in their passage wetted with the spray of the sea, which, when it was dry, left the salt behind it in a fine white powder.

During the period of the war a considerable increase in the prevalence of this pest has been noted. It is no doubt due in part to the use of the public lavatories in trains and railway stations by infected

men.

Hæmatopinus ventricosus, Denny. Rabbit Louse

This louse has probably been here since rabbits were first introduced. In 1889 Mr Coleman Phillips attributed the decrease of the rabbits in South Wairarapa in 1885-86 largely to the prevalence of this insect-pest, in association with Sarcoptes cuniculi.

Hæmatopinus eurysternus, Nitzsch. Ox Louse

This parasite has been reported by the Agricultural Department for many years past, as being common both on cattle, and pigs. The latter occurrence is not given by Colonel Reid, and I think, therefore, that it is doubtful.

Hæmatopinus macrocephalus, Burm. (H. asini). Horse Louse
This species is commonly found on horses all over the Dominion.

Hæmatopinus vituli, Linn. (H. tenuirostris).
Long-nosed Ox Louse

Colonel Reid informs me that this species occurs on cattle in New Zealand; and Mr Miller states that it was met with at Weraroa

in 1917.

Hæmatopinus ovillus, Neumann

In 1906 this louse was found among sheep in the South Island, but was not identified with any described species. Specimens were sent to Dr Neumann who described it (Agricultural Report for 1908, p. 194) under the above name. This species is found among sheep in Scotland, from whence, no doubt, the parasite was introduced, but where it was not previously identified.

Hæmatopinus pedalis, Osborn

Colonel Reid states that this species occurs among sheep in New Zealand.

Hæmatopinus urius, Nitzsch (H. suis, Linn.). Pig Louse

All the authorities are agreed that this louse is very common among pigs in New Zealand.

Hæmatopinus pilferus, Burm. Dog Louse

Dr Reakes and Colonel Reid inform me that this species is common on dogs.

Chapter IX

CRUSTACEA AND ARACHNIDA

CRUSTACEA

(Order ANASPIDACEA, see Appendix B, p. 561.)

Order ISOPODA

Family ONISCOIDA

Porcellio scaber, Latreille. Wood Louse

THIS species, which originally belonged to the more temperate regions of Europe, but has been introduced accidentally by man to nearly all the temperate regions of the world, must have reached New Zealand at an early date, for it was recorded in White's list of New Zealand Crustacea in the British Museum in 1847 as P. graniger. It is now common all over the Dominion, especially in greenhouses and other places near dwellings, but also further from habitations, though not (according to Dr Chilton) in the untouched native bush. Mr W. W. Smith states that the wood lice have largely displaced native ants. He says (1901):

In several parts of this district (Ashburton) the wood-lice have almost displaced the native ants. Instead of finding great numbers of ants' nests, as formerly, under the half-embedded stones, we found their old homes tenanted by swarms of wood-lice.

Armadillidium vulgare, Latreille

Another European species that has been dispersed by artificial means to all temperate regions. In New Zealand it is known from Nelson, where it appears to be common in the town gardens; from Mount Egmont (exact locality not known); and from Sumner, where it is common in some gardens. The date of its introduction into New Zealand is unknown, but it was established in Nelson before 1890.

Metoponorthus pruinosus, Brandt

Dr Chilton says "a species common in Europe and neighbouring countries in rather warmer climates than the two preceding. Also widely dispersed into the warmer portions of the world. Specimens from Tasmania in the British Museum were named Porcellio zealandicus by White in his list, published in 1847, and a similar specimen from New Zealand was obtained in 1854 (but not described till 1876, in Miers' Catalogue of New Zealand Crustacea), so that it must have been introduced before that date, perhaps by whaling ships. It

does not appear to have established itself, and I have specimens from one locality in Hawke's Bay only."

The species is abundant in Norfolk Island, the Kermadecs, Australia, etc.

Order DECAPODA

Sub-order MACRURA

Family NEPHROPSIDÆ

Homarus vulgaris, Linn. European Lobster

The first attempt to introduce the lobster into New Zealand waters was made by the late Mr A. M. Johnson, who left London in 1864 by the ship 'British Empire' with 26 lobsters on board which he obtained from the "Mumbles" in Wales. In a letter to me dated 15th September, 1915, he says: "they developed so pugnacious a disposition that they killed each other; the remaining one I sold to one of the first-class passengers." Mr Johnson evidently kept them altogether in one tank.

In 1885 Mr S. C. Farr, on behalf of the Canterbury Society, put 12 lobsters on board the 'Kaikoura,' but they all died in the tropics. In 1892 Mr Clifford shipped a number from London for the Otago Acclimatisation Society, but "although the experiment was gone into on a somewhat extensive scale, it nevertheless failed."

In 1891 and again in 1892, Mr Purvis, chief engineer of the 'Ionic,' attempted to bring lobsters out to Otago, on both occasions without success. But in 1893 he was successful in landing nine (out of 12 shipped) at Dunedin. These were liberated at the Mole at the entrance to Otago Harbour, a very unsuitable place, but nothing more was ever heard of them.

The next attempt was made on behalf of the Board of the Portobello Marine Fish Hatchery, when arrangements were made with the Marine Biological Laboratory to procure lobsters at Plymouth, and ship them to New Zealand. Four shipments were made on successive trips of the S.S. 'Karamea' in 1906-8, as follows:

In 1908 some 36,000 larvæ were hatched in the tanks; and in the following year about 100,000 were hatched out. In 1910 only 33,000 larvæ were secured in the tanks; but the majority were allowed to hatch naturally in the ponds and the larvæ to escape into the open

sea. This plan has been followed in succeeding years, as it has been found impossible with the other work to be done at the station, to control the rearing of young lobsters. On 1st March, 1913, Mr Anderton, curator of the Station, arrived from Britain in the 'Waimana' with 14 male and 28 female lobsters (out of 43 shipped).

In the following year, to relieve the congestion in the ponds, 12 of the old stock of lobsters (four males and eight females) were liberated at the end of the spawning season, in what was considered to be the most suitable locality in the neighbourhood of Otago Harbour.

In 1914 and succeeding years the female lobsters, numbering about 20, have borne full crops of eggs. It is considered therefore on a moderate estimate, that during the 15 years since lobsters were first introduced at Portobello, more than 1,000,000 fry have been liberated from Otago Harbour. As the young lobsters are free-swimming for the first few weeks of their existence, and as a southerly current averaging a knot and a half per hour flows past the entrance of Otago Harbour, the probabilities are that numbers of them have been carried northwards before they reached the stage at which they sink to the bottom of the sea.

No young lobsters have yet been taken on the coast, but as they take probably seven years or more to reach sexual maturity, and during that time live mostly concealed among rocks and seaweed, the chances of their being captured are few. Any day therefore specimens may be met with.

Family PENAIDÆ

Penæus canaliculatus, W. A. Haswell. Australian Prawn

In 1892 the Wellington Society received some prawns from Captain Wheeler, which he had brought over from Sydney. They probably belonged to this species, which is commonly caught and marketed in Sydney. They were liberated at Nelson, and were never heard of again.

In 1894 Mr Clifford brought over a number (which I identified as belonging to this species) from Sydney for the Otago Society. They were liberated from the mole at the entrance to Otago Harbour, and were not heard of again. The water of the southerly current which washes the south-east coast of Otago is too cold for this species

In July, 1921, the Otago Acclimatisation Society obtained from the Fisheries Department, Melbourne, a number of fresh-water shrimps from some inland waters in Victoria. All were dead on arrival. I do not know what species this was.

Sub-order BRACHYURA

Family CANCRIDÆ

Cancer pagurus, Linn. British Edible Crab

In 1885 Mr S. C. Farr, on behalf of the Canterbury Society, shipped 12 crabs by the 'Kaikoura,' but they all died in the tropics.

No further attempt seems to have been made till the Portobello Fish Hatchery Board decided to introduce them. In August, 1907, there were landed from the 'Karamea,' three male and five female crabs; and on her next voyage in 1908, seven males and one female. The females all bore ova, but no attempt was made to deal with the larvæ as they hatched. They were liberated from the station with the outgoing tide, and considerable numbers were carried outside the Otago Heads and set free at a distance off shore. In this way it was estimated that up to 1912, over 20,000,000 fry had been liberated.

In 1913 there were shipped on the 'Karamea' at Plymouth, 50 crabs (17 males and 33 females), and of these 43 were landed at the hatchery. They did not thrive, however, and no fewer than 16 died at the approach of the cold season. It was therefore thought advisable to liberate most of the remainder, so 19 were set free in a suitable locality, and eight were retained in the ponds. Of these two died the following season. The number of larvæ liberated in 1914-15 was estimated to be 12,000,000. It is probable therefore that some 40,000,000 larvæ have been distributed since the first experimental introduction in 1907. As the larvæ remain in a pelagic condition for a long time, and pass through several metamorphoses, the death-rate must be very high; but making allowance for this the chances are that ere long specimens of this crab will be found on the New Zealand coast.

It has been found very difficult to keep these crabs under observation at the Portobello Hatchery, as they burrow in the mud, get under stones and even under the foundations of the walls of the ponds. It is probable also that the winter temperature of the ponds in Otago Harbour is too low for them, and this may account for the high deathrate. In British seas it is known that they move into deep water at the approach of winter. While the temperature of the open sea outside Otago Heads seldom falls to 50° F. in the middle of winter, that of the Harbour itself often touches 40° F., and in the ponds has been found as low as 32° F. Lobsters can stand these low temperatures, but they appear to be very detrimental, if not always fatal to this species of crab.