1925] Shoemaker, Amphipoda from Gulf of California 51 



These specimens, of which one is male and the other female, agree 

 quite well with Stebbing's figures. The inner ramus of uropod 3 in the 

 male is not pointed as in his figure, but is bluntly rounded; this, however, 

 may be an individual peculiarity, as that of the female is much more like 

 Stebbing's figure. Perseopod 5 of female with second joint not expanded 

 as in male, and with the succeeding portion of the limb proportionately 

 longer. Length of the specimens, 6 mm. 



Platyscelidse 

 I am here using the name Platyscelidse, which was established by 

 Bate in 1862. Stebbing points out that, the genus Typhis having been 

 preoccupied, Platyscelus remains its earliest synonym. Then by right of 

 priority the family must become Platyscelidse from the earliest genus 

 Platyscelus. The family is much more restricted now and does not 

 include the Pronoinx (Dana) as when established by Bate. 



Platyscelus dubius, new species 



Localities. — Cape San Lucas, Lower California, ship's anchorage, electric 

 light; 19 specimens (lcf type). Carmen Island, southeast side, Gulf of California, 

 electric light; 2 specimens. San Josef Island, Gulf of California, electric light; 3 

 specimens. Agua Verde Bay, Gulf of California, electric light; 3 specimens. 



Male. — Head with a depression just above the rostrum. Rostrum prominent. 

 Eyes arranged in four groups. Antenna 1, first joint of flagellum tumid with upper 

 edge short, and lower distal angle rounded and produced, second joint twice as wide 

 as third, but equalling it in length, fourth joint a little longer and a little narrower than 

 third. Antenna 2, third joint nearly straight, fourth a little longer than fifth, first 

 joint of flagellum a little less than half the length of the fifth peduncular joint, second 

 joint of flagellum a little longer than first. Maxillipeds, outer plates short and broad 

 with inner edges slightly concave. Mandible, cutting edge oblique and provided 

 with two rows of small blunt teeth, first joint of palp nearly straight and longer than 

 second, second curved and longer than third, third slightly curved. Gnathopod 1 

 shorter than 2, the produced lobe of the fifth joint serrated on both edges, sixth joint 

 serrated on inner edge. Gnathopod 2, the produced lobe of the fifth joint serrated on 

 both edges and extending a little beyond the sixth joint, sixth joint serrated on inner 

 edge. Perseopods 1 and 2 normal, sixth joint with 2 small teeth just above the dactyl. 

 Perseopod 3, lower edge of second joint evenly rounded; fourth, fifth and sixth joints 

 very nearly equaling one another in length and all with very fine serrations on the 

 front margin. Perseopod 4, second joint with low, blunt tooth near the proximal end 

 of front margin, lower margin oblique and nearly straight, fourth joint widest at 

 distal end and twice as long as fifth, both fourth and fifth with conspicuous serrations 

 on front margin, sixth joint very short and curved. Perseopod 5 nearly as that figured 

 by Claus for Eutyphis ovoides, 1 second joint curved, third joint reduced to a mere knob, 



I'Die Platysceliden,' Taf. I, fig. 9. 



