68 DRS. CARPENTER AND CLAPAREDE ON TOMOPTERIS ONISCIFORMIS. 



Fio-. 6. Second antenna of a young specimen, showing the terminal portion to be setigerous and to be 

 separated from the basal portion by a constriction at a. 



Fig. 7. One of the ordinary lateral appendages, showing the position of the ciliated canal with its two 

 external orifices a,b, and its internal orifice c, and of the " rosettenf brmige Organe" d,d; at 

 e, e is shown the incipient development of the germ-cells in the terminal wall of the perivis- 

 ceral cavity. 



Fig. S. External portion of the ciliated canal, more highly magnified : a, larger ciliated rosette ; b, smaller 

 rosette. 



Fig. 9. Yellow " rosettenformiges Organ" of Leuckart and Pagenstecher. 



Fig. 10. Corpuscles floating in the fluid of the perivisceral cavity, some of them aggregated into masses. 



Fig. 1 1 . Trichocysts or thread-cells in pinnula of one specimen of Tomopteris. 



Fig. 12. Bilobed ganglion, showing the spheroidal cells of which it is composed, with the pair of peculiar 

 nucleated vesicles a, a imbedded in its anterior part, and the ocelli b, b each with its double 

 lens. 



Fig. 13. Germ-cells multiplying by self-division to produce ova. 



Fig. 14. Very early larva of Tomopteris : a, a, the long first antennae; b, b, the short second antennae; 

 c, d, e, f, four pairs of sessile pinnulse, of which c and d show the " rosettenformige Organe." 

 Magnified 65 diameters. 



