416 Annals of the South African Museum. 



longer than the outer in the Lampropida3, whereas in our species the 

 two rami are equal, and in D. tuhulicauda the inner ramus is much 

 the shorter. Dr. Caiman says of the last-named species : " The 

 characters of this peculiar form do not coincide with those of any 

 of the admitted genera of Diastylidae." I venture to think that it 

 will prove to be a species of the new genus here instituted, and that 

 the unique characters of the third maxillipeds and the telson justify 

 the naming of a new family Dicidse. In D. tuhulicauda " the third 

 and fourth thoracic somites are quite distinct from each other," and 

 the third maxillipeds have not been described. 



The generic term here proposed is the literal Latin rendering of 

 Say, the name of the American naturalist who, by his Diastylis in 

 1818, was the first to include any of the Sympoda in a distinctive 

 genus, a scientific feat deserving honourable recognition. 



* Die CALMANi, n. sp. 

 Plates XLVI.B and XL VII. 

 The whole integument is covered with hexagonal markings, the 

 hexagons irregular and unequal. Of the five exposed trunk-seg- 

 ments the first is very short, the second and fifth not very long, the 

 dorsally coalesced third and fourth with well-marked lateral sutures. 

 The pleon is composed of six segments not very unequal, the fifth 

 very little longer than the sixth, and a remarkably long telson. This 

 equals in length the fourth, fifth, and sixth segments combined, and 

 tapers very slightly to the little triangular apex, which is fringed with 

 ten denticles, two of them apical. The dark contents of the intes- 

 tinal canal in the specimen examined extended in a broad stripe to 

 the valves attached at the base of the triangular apex. 



Of the eye I cannot speak with certainty. At the apex of the true 

 rostrum seen laterally a bright transparent tubercle gave the appear- 

 ance of an ocular lens (or lenses), but the real character remained 

 uncertain on dissection. The first antennae have a peduncle of three 

 stout joints, the first the longest. Both flagella are very small, the 

 accessory one minute, two-jointed, the principal four-jointed, the 

 third joint tipped with two filaments longer than the flagellum. 

 The more slender second antennae have a peduncle of three short 

 and two fairly long joints, with an indistinctly five-jointed flagellum, 

 about once and a half as long as the fifth joint of the peduncle. This 

 appendage I take to be the partially developed antenna of a male 

 specimen. 



Upper lip faintly emarginate. Lower lip with subacute, inward 

 pointing, setulose process at the apex of each lobe. One mandible 



