590 Dr. R. von Willemoes-Suhm on Crustacea 



where plentiful beyond 50 fathoms ; nor do I think that Eossella will be 

 found at all in a depth of 25 fathoms. 



The Crustacea inhabiting the shallower water are several species of 

 Serolis, Sphceroma, Arcturus, some G-ammarids, several species of Cajprella, 

 one of which has a very slender and long manus, and some Pycnogonicls. 

 There is scarcely any thing interesting to be fonnd in that zone. In 

 the second zone of deeper water (though not deep-sea fauna, which 

 we scaroely ever have found in less than 500 fathoms) we had a richer 

 harvest; Tanais and Praniza, very curious amphipods, Mysids and Nebalia 

 are the inhabitants, about which I shall now say a few words. 



A Tanais having a length of about 17 millims. is very common, and 

 though not deviating by any means from the typical species of the genus, 

 it has a peculiarity connected with its propagation ; for the females, in- 

 stead of having breeding-lamellae, as the other species of the genus have, 

 carry their eggs, like Copepods, in small cutaneous sacs attached to the 

 genital opening at the base of the fifth pair of pereiopods. These sacs 

 extend as the development goes on, and attain a diameter of 3-4 millims. 

 Professor "Wyville Thomson having discovered among the echinoderms of 

 Kerguelen Land many forms which do not undergo any metamorphosis, but 

 develop in pouches of their parents, this peculiarity in Tanais deserves 

 to be noted, not exactly as comparable to those facts, but as an anomaly 

 in the group to which the animal belongs. 



Less common than this Tanais was an animal which very closely re- 

 sembles the European Anceus maxillaris {Praniza, Leach), of which I got 

 several males and ovigerous females. 



A larger species of Serolis, which is the predominant and most 

 characteristic form of all the Crustacea in the shallow water of the 

 Antarctic islands, was also to be found in this second zone. "With it an 

 Amphipod occurred, a Grammarid, distinguished by a bright red frontal 

 prolongation of the head and having no eyes. These I first thought 

 might be discovered in some form or other in the red proboscis ; but my 

 expectations were not justified by the results of the dissection. The 

 organ is divided by a line along its top into a right and a left portion. 

 The chitinous layer has got no facettes, and the whole organ is filled by a 

 finely granulated red pigment. "What its function may be I cannot say, 

 having never met with any thing like it. 



The Nebalia was very rare. Though I sifted the mud for a long time, 

 and was most anxious to find more specimens of it, I only succeeded in 

 getting two females, which differ from N. Oeoffroyi only in having 

 the borders of the abdominal segment somewhat more sharply denticu- 

 lated. Until, however, the male is known I do not think it right to 

 declare it to be the same species. 



Besides a small Cuma, which was very common, we found in the deeper 

 zone outside Christmas Harbour the only decapod which was brought 



