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



Maria, we got from a depth of 1000 fathoms another Anisopod, which belongs to the 

 interesting genus Apseudes, according to Mr. C. Spence Bate* the only Isopod in which 

 the antennal scale, so common in the Macrura, is present on the lower antennae, and, as 

 we may add, one of the few in which there are two fiagella in the anterior antenna. 

 In the species of Apseudes hitherto known the eyes are pedunculated : in this deep-sea 

 animal there are no eyes at all ; hence we might call it A. cceea. It has a length of 

 6 millims., the females having the same length as the males. 



The cephalothorax, to which is attached the first pair of gnathopods, has a spiny 

 rostrum and two prominent spines on each side. The first antennae (fig. 1, a\ and fig. 2) 

 show a very strong funiculus and two fiagella, one of which consists of twenty-four, the 

 other of eight joints. The longer is double the length of the smaller one. 



The exterior or second antenna? (fig. 1, a 2 , and fig. 3) have a smaller fiagellum, con- 

 sisting of eight joints and an antennal scale articulating with the first joint of the 

 funiculus (fig. 3, s). The mandibular have a palpus consisting of several joints. 



The maxilnped (fig. 9) has strong tufts of hairs on the last three joints. The two 

 gnathopoda are very different in form : the first one (fig. 4) is short, and terminates 

 in a strong recurved chela; while the second is much longer (fig. 5), and has enlarged 

 and flattened joints with strong spines, as may also be seen in the other species of 

 Apseudes. The pereiopoda are strong but not very much enlarged appendages. We 

 have drawn the first and second as well as the top of the fourth ; the third is terminated 

 by a bifid claw, as is the sixth in A. talpa, Mont., which we have not drawn, as only 

 once could we clearly get sight of it. When afterwards it was tried again to get a view 

 of the two claws, it was impossible to separate them from each other. 



The first five segments of the pleon are short, and possess small biramous pleopoda. 

 The last segment is elongated, as in A. talpa, and shows at the top two pairs of caudal 

 setae. 



In the females there are breeding-lamellae at the base of the second gnathopoda and 

 the first two pereiopoda, which are wanting in the males. -This is the only difference 

 which I could find out between the two sexes. 



Most of the specimens which we got were washed out from the mud which the. dredge 

 had brought up. We did not meet with this Crustacean again. 



This is not the first instance of blind Isopods being described, as some subterranean f 

 and parasitical % forms are well known to have no eyes, or to lose them, as Ancem does, 

 when getting old. There is also a whole family, the Munopsidse, which is blind, though 

 most of its members live in moderate depths. A very large member of this family 

 has also been got by us in the deep sea ; it cannot, however, be described now, as the 

 necessary literature is not at hand. 



II. On Ctstisoma Neptunus [Tbaumops pellucjda). (PL XI. figs. 4—8.) 

 In a postscript to my paper on Tliaivmops pellucida (Phil. Trans, of the Royal So- 

 ciety, 1873) I have described the male of this remarkable Amphipod, and given some 



* Facts and Arguments for Darwin, by Fritz Muller, translated by Dallas (London), 1869, p. 132. 



f Titaneihes albus and Typhloniscus Steinii. J Bopyrida and the female of Aneeus. 



