22 Bulletin American Museum of Natural History [Vol. LII 



Lycsea bajensis, new species. San Josef Island. 

 " " " Cape San Lucas. 



" " " " Carmen Island. 



Parascelus zebu Stebbing. Carmen Island. 

 Platyscelus dubius, new species. Cape San Lucas. 

 " " " " Carmen Island. 



San Josef Island. 

 Agua Verde Bay. 

 Tetrathyrus sancti-josephi, new species. San Josef Island. 

 " " " Agua Verde Bay. 



Carmen Island. 

 Amphithyrus orienlalis Stebbing. San Josef Island. 



Gammaridea 

 Phoxocephalidse 



Heterophoxus, new genus 



Body not very broad. Head with evenly vaulted hood, not carinate or deflexed. 

 Eyes well-developed. Side-plates plumose, fourth broadly produced backward, 

 fifth with oblique hind lobe. Eyes very large, oval, black. Antenna 1 in cf, first 

 joint very large, flagellum in o* 1 with calceoli and sensory clubs. Antenna 2 in cf, 

 lower anterior corner of second joint produced into a prominent lobe, flagellum nearly 

 as long as body, fifth joint and flagellum with calceoli. Mandible, cutting edge and 

 spine-row well developed, accessory cutting plate present, molar feeble, tipped with 

 three spine-teeth, palp linear with few setae, third joint very little shorter than second. 

 Maxilla 1, palp 1-jointed, well developed, inner plate well developed with two setae. 

 Maxilla 2, plates subequal. Maxilliped, outer plate reaching nearly to middle of 

 second joint of palp, inner plate obtusely rounded at apex, third joint of palp not 

 produced, fourth very short, tipped at apex with two long curved spines. Gnatho- 

 pods and peraeopods much as in Harpinia. Peraeopod 3, second joint not expanded. 

 Peraeopod 4 much longer than the rest, second joint narrowed distally. Peraeopod 

 5 rather small, second joint much expanded. Uropod 3 in c? well developed, outer 

 ramus the shorter and both rami bearing long, plumose setae. Telson rather short and 

 broad, cleft a little over half its length, lobes broadly rounded apically. 



Heterophoxus pennatus, new species 



Type Locality. — Pichilinque Bay, Gulf of California, March 28-29, 1911, 

 electric light; 2 specimens (1 cf type). 



Male. — Head with evenly vaulted hood, broadly rounded in front and reaching 

 just beyond the end of the second joint of antenna 1, postero-antennal angles quad- 

 rate. Eyes large, oval, black, and nearly meeting at top of head. Antenna 1, first 

 joint very large, provided on the lower anterior corner with numerous sensory bristles 

 and several plumose setae, second joint about half the length and width of first, third 

 joint about half the length and width of second, flagellum about the length of the 

 first joint of the peduncle and composed of eight joints which are provided with 

 sensory clubs and a few calceoli, accessory flagellum half the length of the primary and 

 composed of five joints. Antenna 2 nearly as long as the entire animal, second joint 



