_66_ 



Remarks. This genus was established as early as the year 1839 by 

 Philippi, to include the species described below. The genus Oniscidium of Glaus 

 is unquestionably identical with Philippi's genus, as is also the genus Reticulina, 

 recently established by Prof. Cleve. The genus is especially characterised by the 

 very conspicuous net-work of chitinous stripes strengthening the body, as also by 

 the unusual development of the epimeral plates of the last segment of the meta- 

 some and the 1st of the urosome. Of the several appendages, the anterior max- 

 illipeds and the 1st and last pair of legs in particular are of a characteristic 

 structure. In addition to the typical species, 5 new species have recently been 

 recorded by Mr. A. Scott from Ceylon. The form described by Prof. Cleve as 

 Reticulina aurivilli from the Malay Archipelago is in all probability identical 

 with one of these species. 



40. Peltidium purpureum, Philippi. 



(PL XXXIX & XL). 



Peltidium purpwenm, Philippi, Wiegmann's Arcliiv f. Natuvgeschichte 1839, p. 131, PI. IV, 



figs. 12, 13. 



Syn: Oniscidium armatum, Claus. 



Specific Characters. Female. Body, seen dorsally, oval quadrangular in 

 outline, greatest width in front of the middle and exceeding half the length. 

 Cephalic segment very large, occupying nearly half the body, postero-lateral 

 corners acutely produced, frontal margin angular on each side, rostrum large 

 and prominent, transversely truncated at the tip. Free segments of metasome 

 each produced dorsally in the middle to a triangular, posteriorly-pointing pro- 

 jection; genital segment with 2 similar dorsal projections. Epimeral plates all 

 of uniform appearance, tongue-shaped and curving posteriorly; those of genital 

 segment extending beyond the extremity of the urosome, and having a much 

 smaller acute lappet behind. Caudal rami far apart, sublinear in form, the inner- 

 most but one of the apical seta? much coarser than the others, and exceeding the 

 urosome in length. Anterior antennse not attaining half the length of the cephalic 

 segment, 7-articulate and densely setiferous. 1st pair of legs with the 2nd joint 

 of the outer ramus somewhat longer than the 1st, last joint small and armed 

 with 3 strong claws and a curved seta; inner ramus of about the same length 

 as the outer, distal joint fully as long as the proximal one and provided at the 

 tip with 2 equal-sized setae, and at the inner edge with a much coarser ciliated 

 spine. Last pair of legs with the distal joint evenly curved, and armed with 6 

 strong ciliated spines, 3 of which issue from the outer edge. 



