402 On Tico new Amphi pods from (he West Indies. 



tlie first joint, and is almost devoid of setules. The marsupial 

 lamina? in the female are large, with short filaments, chiefly, 

 though not exclnsivelj, on the first pair. The specimen figured 

 had four large eggs in the slightly dehiscent marsupium. 



Third^ Fourthj and Fifth Perceopods. — These limbs are 

 similar in structure, but the fourth are of larger size than the 

 third and the fifth than the fourth. The hand is powerful, 

 with a projection at the base, against which the long curved 

 finger impinges. The basal process is followed by four or 

 five of like character, but successively decreasing in size, 

 along the inner margin. This form of hand is noticed by 

 JNJayer as occurring not only in Deutella venenosa, but also in 

 the genera Paracaprella and Hemicegina. 



The length of the male specimen is three-twentieths of an 

 inch, the antennse and limbs not being included. The females 

 with eggs are rather shorter. A specimen from which the 

 mouth-organs separately figured were dissected was smaller 

 than the females ; it had the appearance of being a young 

 male. 



The specific name is given out of respect to Dr. Paul 

 Mayer, whose works on this branch of Crustacea can scarcely 

 be too highly appreciated. 



The specimens were taken from sand in shallow water at 

 Antigua by Mr. W. R. Forrest. Since Mayer's Deutella 

 venenosa was taken at Coquimbo, on the west coast of South 

 America, along with Caprella scaura, Templeton, it may be 

 worth mentioning as a coincidence that along with the present 

 species Mr. Forrest sent also a specimen of Caprella scaura. 

 Moreover, he sent a specimen which appears to belong without 

 doubt to the species named j^ginella tristanensis in the 

 Report on the ' Cliallenger ' Amphipoda. This species has 

 since been referred by Dr. Mayer to a new genus, Pseud- 

 ceginella. The ' Challenger ' specimen was destitute of all 

 the last three pairs of per^eopods : the specimen from Antigua 

 has them all. In general appearance they are not very unlike 

 those of Deutella 2layeri, though the inner margin of the head 

 is simpler ; but they have one character which is very unusual, 

 namely, that the penultimate pair is notably larger than the 

 ultimate. Additional specimens may hereafter show that this 

 is only a casual variation. 



EXPLANATION OF THE PLATES. 



Plates XIV. & XV. B. 



Amphithoe megaloprotopus. 



Lateral view of the annual ; the natural size indicated by the line above. 



«.•«., upper antennae ; a.i., portion of lower antenn* ; is., upper lip ; m, m, 



