264 



CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. I. 2. 



HYPERIID^E. 



4. PARATHEMISTO TRIGONA, J. D. DANA, 1852. 



Parathemisto trigona, J. D. Dana. 

 Facsimile from Dana. U. S. Expl. Exp. Crust. II, pi. 67, fig. 12. 



Fig. 1. The animal from the side. 2. The maxillipeds. 4. The first pair of perreopoda. 4. The second pair. 

 5. The fourth pair. 6. The fifth pair. 7. The urus. 8. The last pair of uropoda. 



Diagll. Corpus carinatum. Caput segmentis duobus primis perasi paullo longius. Carpus pedum percei 

 primi paris metacarpo multo longior; margo anterior levis, margo posterior spinis armatus; 

 margo posterior metacarpi non serratus(P), spinam unam gerens; dactylus dimidio meta- 

 carpi brevior. Metacarpus pedum secundi paris carpo multo longior; processus carpalis 

 tres partes metacarpi longitudine requans, spina terminali carens; dactylus dimidio meta- 

 carpi brevior. Metacarpus pedum tertii ac quarti parium carpo non longior. Metacarpus 

 pedum parium trium ultimorum articulis duobus praeeedentibus longior. Pedunculus pedum 

 uri ultimi paris quam telson quater longior; ramus internus externo longior. 



The body is carinated. The head, is a little longer than the first two pergonal segments to- 

 gether. The carpus of the first pair of perceopoda is much longer than the metacarpus; 

 the front margin is smooth, the hind margin is armed with bristles; the hind margin of 

 the metacarpus is not serrated (?) and has a single bristle; the dactylus is not half as long 

 as the metacarpus. The metacarpus of the second pair is much longer than the stem of the 

 carpus; the carpal process, is three-fourths as long as the hind margin of the metacarpus, and 

 wants a terminal spine; the dactylus is not half as long as the metacarpus. The meta- 

 carpus of the third and fourth pairs is not longer than the carpus. The metacarpus of the 

 last three pairs is longer than the two preceding joints together. The peduncle of the 

 last pair of uropoda is four times as long as the telson; the inner ramus is longer than 

 the outer. 



