South African Crustacea. 59 



is a little projecting point at the middle of the apical margin, and the 

 sides are crenulate as if in reminiscence of earlier segmentation. 

 But these characters, which Hansen does not notice, only became 

 conspicuous after the pleon had been detached. The stilet-like 

 mandible shows a microscopic serration at the distal end. The 

 almost linear maxilliped has a terminal seta. 



The male has a faint greenish tinge, as contrasted with the pallid 

 colour of the female. The relation of these tints to the colours of 

 the living animals is uncertain. 



Size. The female measures 11 mm. in length, and about the 

 same in breadth. The male attains the unusual length of 8 mm., 

 with a breadth of 2-5 mm. 



Locality. Cape Point N.E. by E. E. 40 miles ; depth, 800-900 

 fathoms; bottom, green mud. In Glyphocrangon sculptus (S. I. 

 Smith). 



AMPHIPODA. 



GAMMARIDEA. 

 FAMILY LYSIANASSID2E. 



For the families in this tribe a general reference may be given to 

 Das Tierreich, Lieferung 21, 1906. But continually additions are 

 being made to the number of genera and species. 



GEN. TKISCHIZOSTOMA, Boeck. 

 1853. Guerinia (preocc.), Hope MS., Costa, Fauna Eeg. Napoli, 



Apr., 1853, p. 1. 



1861. Trischizostoma, Boeck, Forh. Skand. Naturf., Mode 8, p. 637. 

 1893. Guerina, Delia Valle, Fauna und Flora des Golfes von Neapel, 



vol. xx., p. 775. 



1905. Guerinella, Chevreux, Bull. Mus. Monaco, No. 35, p. 7. 



1906. Trischizostoma, Stebbing, Das Tierreich, Amphipoda, p. 12. 

 The rather rare crustaceans for which Hope and Costa, in 1853, 



established the genus Guerinia present some remarkable and some 

 still perplexing features. The original generic name being pre- 

 occupied must be relinquished. In my opinion its place should be 

 taken by Trischizostoma, which was independently denned by Boeck 

 in 1861. That author thought it advisable to assign it to a distinct 

 tribe, Prostomatae, which, however, he subsequently reduced to a 

 family, Prostomatidse. In the meantime Lilljeborg had named a 



