1925] Shoemaker, Am phipoda from Gulf of California 45 



Male. — These specimens agree very closely with Symprone parva (Claus) and 

 Symprone propinqua Stebbing, hut differ from both of these species in a few well- 

 marked characters. The front angle of the head is a»little more acute. Antenna 1, 

 first joint of flagellum somewhat wider and produced into more of a lobe distally; 

 second and third joints subequal in length, fourth joint very slender and a little longer 

 than third. Antenna 2, fifth joint of peduncle a little shorter than fourth, first joint 

 of flagellum over half the length of the third joint of peduncle and less than half the 

 length of the fifth, second joint of flagellum very small, third joint of flagellum shorter 

 and narrower than second. Maxillipeds much shorter proportionately than in S. 

 parva. Other mouth-parts agreeing with those of S. parva. Gnathopod 1, joints 

 shorter and broader proportionately than in either S. parva or S. propinqua. Gnatho- 

 pod 2 with upper distal end of fifth joint somewhat produced. Peraeopod 4 with 

 second joint not distally rounded, but slightly emarginate. Peraeopod 5 with second 

 joint as in S. parva, but with three narrow terminal joints instead of two, the.first of 

 these joints short, the second longer and somewhat narrower, and the third narrower 

 and longer than the second, this last joint varies in length being in some cases little 

 longer than the preceding and in others nearly twice as long. Uropods and telson 

 much as in S. parva except that the telson is obtusely pointed and is one-fourth wider 

 than long. 



Length. — 7 mm. 



Brachyscelidae Stephensen, 1923 

 Brachyscelus crusculum Spence Bate 



Brachyscelus crusculum Spence Bate, 1861, Ann. and Mag. Nat. Hist., (3) 

 VIII, p. 7, PI. ii," figs. 1,2. 



Brachyscelus crusculum Spence Bate, 1862, 'Brit. Mus. Catal. Amph. Crust.,' 

 p. 333, PI. liii, figs. 2, 3. 



Thamyris crusculum Bovallius, 1887, 'Systematical List of Amph. Hyper.,' 

 Bihang till K. Svensk. Vetensk.-Akad. Handl., XI, No. 16, p. 31. 



Thamyris mediterranea Claus, 1887, 'Platysceliden,' p. 60, PL xvi, figs. 11-18. 



Brachyscelus crusculum Stebbing, 1888, 'Challenger Amphipoda,' p. 1544, PI. 

 cxcv, specimen a. 



Brachyscelus crusculum Chevreux, 1893, Bull. Soc. Zool. France, XVIII, pp. 

 70-74, text figs. 1-9. 



Brachyscelus crustulum Norman, 1900, Ann. Mag. Nat. Hist., (7) V, p. 134. 



Brachyscelus crusculum -\-B. mediterraneus Chevreux, 1900, 'Res. Camp. Sci. 

 Monaco,' Fasc. XVI, p. 153, 154. 



Brachyscelus mediterraneus Senna, 1903, Ann. Mus. Zool. Napoli, (N. Ser.) I, 

 No. 6, p. 5. 



Brachyscelus crusculum Tattersall, 1906, Fisheries, Ireland, Sci. Invest., 

 1905, No. 4, Pt. 8, p. 26. 



Brachyscelus crusculum Holmes, 1908, Proc. U. S. Nat. Mus., XXXV, p. 490. 



Brachyscelus crusculum Stephensen, 1923, 'The Danish Ingolf-Exped.,' Ill, 

 'Crust. Malacos.,' V (Amphipoda. 1), p. 37. 



Cape San Lucas, Lower California, ship's anchorage, electric light; 

 5 specimens. Carmen Island, southeast side, Gulf of California, electric 

 light; 1 specimen. San Josef Island, Gulf of California, electric light; 



