68 Annals of the South African Museum. 



pared with a large female specimen from Australia. The specimens 

 obtained by Dr. Gilchrist in South Africa include fully developed 

 males and other individuals of which it is desirable that some notice 

 should be taken. 



In the mature male the eyes are very conspicuous by their dark 

 colour and considerable size. They are rather broader above than 

 below and are almost contiguous on the top of the head. The first 

 antennae have the first joint large with two blunt apical teeth, the 

 second and third joints short, the principal flagellum rather stout, 

 28-jointed, the calceoli small, its first joint by far the largest, 

 furnished with a brush of filaments ; the secondary flagellum 8-jointed. 

 The second antennae have the first three joints very short, the fourth 

 large, the fifth short, carrying a slender, calceoliferous, 74-jointed 

 flagellum, which reaches beyond the pleon, making the whole of this 

 pair between two and three times as long as the first pair. 



The upper and lower lips are not easily detached one from the 

 other. The upper lip appears to have a bilobed margin. The 

 mandibular processes of the lower lip are long and narrow. In the 

 mandibles the spines of the spine-row are excessively short, and 

 the molar is a thin backward-directed roughly triangular plate, 

 fringed with setules. The second joint of the palp is the longest, 

 and this in its upper half is fringed with some 14 slender spines. 

 M. Bonnier found no armature on this joint in his A. pulchella, nor 

 did I in A. bathycephalus, A. haswelli, or the small specimen of A. 

 macrophthalmus. It may be noted that the triturating organs, or 

 cardiac folds of the stomach, are more circular than usual, and are 

 fringed with slender spines. But this is no speciality of the male. 



The first and second peraeopods are distinguished by having the 

 fourth and fifth joints fringed along the hind margin with long stiff 

 setae, which are not seen in the female or young male. 



In the third segment of the pleon the postero-lateral notch is 

 higher up than in the young. The third uropods have the subequal 

 lanceolate rami fringed with long plumose setae on the inner margin, 

 and the inner ramus is fringed on the lower part of the outer 

 margin. 



A specimen, about 7 mm. long, presumably not fully adult, 

 showed the following differences. The eyes were much more 

 slender, uniform in breadth, pale in colour. The first antennae have 

 the two distal teeth of the first joint acute, the principal flagellum 

 26- or 27-jointed, with the first joint of much less length than in the 

 other specimen, and the secondary flagellum seven-jointed. The 

 second antennae are no longer than the first, with a flagellum of 



