200 



THE MICROSCOPE AND ITS REVELATIONS. 



PLATE XXIIL 



STRUCTURE AND DEVELOPMENT OP TOMOPTERIS ONISCIFORMIS (Original). 



A. Portion of caudal prolongations, containing the spermatic sacs, a, a. 



B. Adult Male specimen. 



c. Hinder part of adult Female specimen, more enlarged, showing ova lying freely in the perivis 

 ceral cavity and its caudal prolongation. 



D. Ciliated canal, commencing externally in the larger and smaller rosette-like disks, a, 6. 



K. One of the pinnulated segments, showing the position of the ciliated canal, c, and its rosette- 

 like disks, a, 6; showing also the incipient development of the ova, d, at the extremity of the seg- 

 ment. 



F. Cephalic Ganglion, with its pair of auditory (?) vesicles, a, a, and its two ocelli, 6, 6. 



o. Very young Tomopteris, showing at a, a the larval antennae; 6, 6, the incipient long antennae 

 of the adult; c, a, e, /, four pairs of succeeding pinnulated segment, followed by the bifid tail. 



