444 Dr. R. 0. Cunningham o?i the Zoology of 



with whose curious form I had long been familiar from figures. 

 This animal occurs plentifully about Sandy Point, and was 

 taken in hundreds in our seine. When on the ground, it crawls 

 along very sluggishly ; but I have seen it paddling rapidly on 

 its back along the surface of shallow pools. The same day I 

 found numerous fragments of a large spiny Lithodes, very 

 closely resembling our L. aixticus, about which we had some 

 correspondence a year or two ago. This and another species 

 of the same genus, which is not nearly so spiny, the spines 

 being replaced in great part by tubercles, appear to be two of 

 the most abundant Crustacea in the eastern part of the Strait. 

 In both, as in all the other foreign species of Litliodes which 

 I have had an opportunity of examining, the pleon is formed 

 on the same plan as that of our British one ; i. e. in the male 

 the plates are symmetrical, while in the female they are pro- 

 minently asymmetrical. I got a small male specimen of what 

 I think may be a third species, at Port Famine, one day we 

 spent there. I procured several other Decapoda in the Strait, 

 a small Munida [App., IV.] among the number, and a variety 

 of sessile-eyed Crustacea, though not so many as I anticipated. 

 I got one or two Nymphons and a species of Hyperia [App., V.]. 

 We left the Strait about the middle of February for the Falk- 

 land Islands, to get fresh supplies of provision and coal, and 

 reached Stanley Harbour in the course of three days. While 

 we were there, the weather was very broken, so that I could 

 not accomplish any long excursions ; but, as far as I could 

 judge, there appears to be a very great similarity between the 

 fauna and flora of the Falklands and those of the Strait. We 

 left Stanley on the 2nd of March, and on the following day, 

 in the forenoon, we noticed several brilliant scarlet-coloured 

 patches in the water floating past the ship. We investigated 

 their nature by means of a bucket let down over the side, 

 and found they were composed of multitudes of a small nia- 

 crurous decapod which swam rapidly about by rapid flexions 

 and extensions of the tail, the movement being backwards, as 

 in our common lobster. I preserved several sjiecimens of the 

 animal, besides making a sketch of it [App., VI. ; PI. XXI. 

 fig. 2] , which I send to you. The entire length of the crustacean, 

 when the tail, which was ordinarily curved underneath the 

 body, was extended, was about three-fourths of an inch ; and 

 the limbs bearing the chelae were nearly an inch long. The 

 general colour was scarlet, the eyes, a large patch on the 

 carapace, and a line extending along the abdominal segments 

 bluish black. I have not been able to identify the animal from the 

 descriptions I have with me. I ought, however, to state that 

 I have a very small stock of books at hand. Captain Mayne 



