GONADS OP CEPHALODISCUS HODGSONI. 57 



only of the protoplasm. Ou the pellicle Ijreaking, the secretiou will flow over 

 the surface of any solid body to which that particular part of the epidermis 

 of the end-bulb is applied, and subsequently solidify as a film. If, however, 

 the animal is killed before the pellicle breaks, the secretion hardens as a clear 

 bead, projecting to a greater or less extent above the general surface of the 

 epithelium (figs. 33-36). I have not recognised any rhabdites in these beads in 

 either C. hochjsoni or C. dodecaloplaif!. 



The refractive beads are not confined to the end-bulbs. Small ones are mostly 

 to be found at the ends of the pinnules, and others, not smaller than those of the 

 end-bulb, may sometimes be seen along the neural face of the plume-axis. More 

 rarely they are to be found in the whole of the epidermis of the body-wall (e.g. in 

 the plumeless polypide referred to above, fig. 52, plate 6). Assuming that these are the 

 cells of the epidermis secreting the test, the inconstancy in their occurrence elsewhere 

 than in the end-bulbs may be accounted for by the relative activity or quietude of 

 the polypide in respect of secretion of test at the time of death. 



Post-oral Lamella. 



The post-oral lamella does not differ materially from that of C. dodecalophiis. 

 It may be described as consisting of a pair of lateral flaps of the body, containing 

 an extension of the collar coelom, situated at the sides of the mouth, and connected 

 behind the mouth by a narrow band which has a free posterior border continuous 

 with the free edges of the lateral flaps, but differing from the latter in not being 

 thickened (fig. 53, plate 6). The post-oral lamella becomes free from the body around 

 the edge of the part which in fig. 53 is shaded by irregular lines, and in the middle of 

 which the mouth is situated. The ragged front edge of the shaded area marks the 

 position of the hinder surface of the stalk of the buccal shield. The base of the 

 sixth plume-axis occurs in development at the anterior limit of the attachment of the 

 lateral flap, and in continuity with it. 



Gonads. 



The sexes of the polypides of Cephalodiscus hodgsoni are in most cases distinct, 

 though not invariably so. Two hermaphrodite polypides, each with one ovary and 

 one testis, were discovered among the many polypides dissected. 



Most of the polypides are females. The ovaries, when fully mature, are ovoid 

 or pyriform bodies, measuring -8 by -5 mm. (fig. 42, plate 5). The oviducts are of a 

 brilliant red colour. In some young ovaries the oviduct is larger than the ovary 

 itself (fig. 43), and the transition from the red oviduct to the white ovary is 

 abrupt (figs. 43 and 46). In other young ovaries the red pigmentation spreads 

 in an irregular and diffuse manner into the interior of the ovary (figs. 44 

 and 45). 



