South African Crustacea. 265 



1880. Axius, Boas, Vid. Selsk. Skr., ser. 6, pt. 1, pp. 98 (76), etc. 



1895. Faxon, Mem. Mus. Comp. Zool., vol. 18, p. 103. 



1901. M. J. Rathbun, U.S. Fish. Comm. for 1900, vol. 2, p. 95. 



1903. Borraclaile, Ann. Nat, Hist,, ser. 7, vol. 12, pp. 536, 549. 



1906. M. J. Eathbun, U.S. Fish. Comm. for 1903, pt. 3, p. 893. 



1914. Balss, Abh. K. Bayer. Ak. Wiss., Suppl., vol. 2, pt. 10, 



p. 85. 



1918. Kathbun, Bull. 103, U.S. Nat. Mus., p. 135 (fossil). 



AxiUS LONGISPINA, 11. Sp. 



Plates CVlB and CVII. 



The character to which the specific name refers, though not super- 

 ficial, deserves to be particularised. The vibratory lamina of the 

 second maxilla ends in a spine equal in length to all the rest of the 

 organ. Boas figures a spine in the same position for his Axius princeps, 

 but he gives it a length less than a third of the maxilla that carries it, 

 and he does not seem to attribute any importance to so unusual a 

 feature. Apart from this the two pairs of maxillae are in near 

 agreement with those of A. princeps, and the same remark applies to 

 the first and second maxillipeds except that in the former the exopod 

 has no such distal narrowing as that shown in Boas's figure. In the 

 long third maxillipeds the fourth joint is considerably longer than 

 the third and only a single tooth diversifies its very setose margin. 



Not only from A. princeps, but from many other species which have 

 been assigned to Axius or its various sub-genera, the present appears 

 to be distinguished by the third and fourth peraeopods, in which the 

 sixth joint has a much greater width than that of the fifth joint, being 

 a very broad oval in the third pair and in both densely fringed with 

 setae. In the fifth pair the sixth joint is not oval, but a little 

 widened distally. In all three pairs the finger is small, not unciuate, 

 but in the fourth pair a little curved. 



Of the first antennae the first joint about equals the second and 

 third combined ; the two flagella are equal in length, the thicker 

 slightly thickening near the end. The second antennae have a small 

 acicle and a slender flagellum about once and two-thirds as long as 

 the flagella of the first pair 



The right-hand eheliped of the first pair is missing ; that on the 

 left was probably the larger, being rather massive, with the movable 

 finger curved, its tip crossing that of the slender thumb, which has 

 a setiferous projection one-third of the length from the apex and a 



