68 
Psyche 
[June-Sept. 
Cook, the genotype. Head conspicuously convexly bulging 
at the sides, with anterior margin angled at middle and 
posterior margin straight. 
The antennae more definitely clavate than in mexicanus , 
the distal half being considerably thicker than the filiform 
proximal half of the organ; distinctly geniculate. 
Prehensors when closed nearly even with anterior margin 
of head; claws slender; prosternum with chitinous lines 
distinct, the anterior border deeply angularly excavated at 
middle. 
Porigerous areas of ventral plates circular, one close to 
each lateral margin and caudad of middle of plate, this 
elevated porigerous area relatively smaller than in ribauti, 
but clearly larger than represented for mexicanus and very 
much closer to the caudal margin of plate. 
Dorsal plates densely coarsely granular, not sulcate. Last 
dorsal plate covering pleurse from above, elongate shield- 
shaped. 
Last ventral plate somewhat longer than wide, narrowed 
caudad, a longitudinal median depression. Pores of coxo- 
pleurse typical. 
Last legs strongly crassate, but narrowing distally. 
Pairs of legs 69 in the three type specimens. 
Length of holotype, about 45 mm. 
Locality. — Panama : Barro Colorado Id. Three specimens 
of which the holotype, a male, was taken July 18, 1988. 
Diplethmus ribauti, sp. nov. 
Diplethmus mexicanus Ribaut (not of Cook), Mem. Soc. 
Neuchatel, vol. 5, p. 90, figs. 26-37. 
Diplethmus mexicanus Chamberlin (not of Cook), Occ. 
Papers Mus. of Zool., Univ. of Michigan, 1921, p. 17. 
Prof. Ribaut, in the place above cited, has given a detailed 
and fully illustrated account of this species. Cook’s descrip- 
tion of mexicanus , embraced in a key, is confined to the 
following: “Ventral pores in two areas; antennse subfili- 
form; Genus Diplethmus, type D. mexicanus, sp. n. (PI. 
V, fig. 2), Mexico.” The figures given are the only means 
of identification. The differences these show in size of the 
