48 DR. R. V. WILLEMOES-SUHM ON SOME ATLANTIC 



if not quite directly concerning our subject, at least touches it ; for the animal I am 

 to speak about is the freshwater crab of Southern Europe, Telphusa fluviatilis. In the 

 mountains above Spezzia I caught some specimens at a spring coming out from the Bocca 

 Lupara ; and one of these being a female, carried with it nearly 150 young ones under 

 the abdomen, the smallest of which had a length of 3 millims. I think this shows clearly 

 that also Telphusa is, with Gecarcinus and Astacus, one of the few Decapods which 

 develop directly without metamorphosis. 



VI. On a blind deep-sea Astacus. 

 (Plate X. fig. 1.) 



In a very successful haul on the 15th of March near Sombrero Island, W. L, we got, 

 from a depth of 450 fathoms, a blind Astacus, one of the claws of which is developed to 

 an extraordinary extent. In the notes which I gave about it to Professor Thomson, I 

 have called this animal Astacus zaleucus ; for, strange as it may seem at first sight, there 

 is no reason for separating this animal from the genus Astacus, except perhaps the want 

 of the eye and its pedunculus. The male of Astacus zaleucus has a length of 110 millims., 

 the cephalothorax having a length of 50, the abdomen of 60 millims. 



The carapace is laterally very much compressed, and divided by a deep transverse 

 sulcus into two portions or regions. At the top of the anterior one is the rostrum, 

 having a length of 9 millims. Its borders have six small teeth. Before the rostrum there 

 are two large triangular patches, which are densely covered with short hairs ; and these 

 continue from both sides towards the rostrum. On both sides of the anterior portion 

 there are besides several small spines, and two sulci, which establish again a small mar- 

 ginal and triangular subdivision. The posterior portion of the carapace can also be 

 subdivided, into a quadrangular upper portion and two lateral regions. The last segment 

 of the pereion is in articulation with the carapace, quite in the same way in which it is 

 in all Aslaci, 



On both sides of the rostrum there are two vacant places, where in other species the 

 pedunculus of the eye is fastened. Here there is not a trace of it. 



The four-jointed funiculus of the antenna interior bears two very hairy nagella, of the 

 length of 40 millims. The base of the antenna exterior terminates on one side in a sharp 

 spine. The squamiform appendage is somewhat curved outwards, reaches the middle of 

 the second funiculus-joint, which is rather long, and has at the inner side eight sharp 

 spines. The flagellum of the antenna exterior has a length of 130 millims. Underneath 

 its base the large opening of the " green gland " is clearly to be seen. 



The margin of the upper lip is somewhat tilted upwards, and beset with 6 small 

 spines. About the mandible I have nothing particular to say. The chewing-plates of 

 the first maxillse are very strong, and the palpi of the maxillipedes very large. They look 

 nearly like a ramus of one of the swimmerets. The palpi of the two gnathopods, 

 however, have the ordinary form. The second gnathopod has thrice the length of the 

 first one. 



The pereiopods are all very hairy, especially their first two joints, which, with the 



