DI.KX'w:. \STMI 7 



continued along the dorsal wall >f the pericardium ; consequently it is situated ventrally 

 fn>m the atrium. The blood of the atrium in driven into the ventricle through one 

 large opening, there being no question of two atrio-ventricular openings. The wall of 

 both parts of the heart here also remains thin ; it is strengthened by muscular fibres 

 belonging to the surrounding tissue. The ciliated bands (" bourrclets cilies " of 

 Pruvot) do not fail, at least not in the distal part of the pericardium (Fig. 22, <>>). The 

 irl.u i vi-ly very large blood-corpuscles are of a peculiar shape, oblong, more or less 

 [x.inted corpuscles of various forms. They stain pale-red with carmalum and usually 

 have a small round nucleus, which may occur at different points, and often obviously 

 protrudes (Fig. 26, A). Further, there occur in the blood large round cells with round 

 granular nucleus (Fig. 26, B). 



The animal in mature ; the gonads extend to close behind the radii la. The eggs 

 are formed on the median walls, the spermatozoa on the dorsal, ventral, and lateral walls. 

 Both the gonads are densely filled with products, more especially the distal part, which is 

 entirely filled with eggs, or rather with generative epithelium. The latter seems to 

 become free in the gonads ; in the pericardium, compact masses of small round cells occur 

 (Fig. 25, A), which arc also found on the median walls of the gonads, and which prolwbly 

 belong to the generative epithelium. Amongst these large cells mature eggs arc 

 observed, with granular contents and of various sizes (Fig. 25, B) ; even very large eggs 

 are found, though they are of rare occurrence. Such eggs are often surrounded by the 

 small cells of the generative epithelium, enveloping them like a follicle. Further, 

 numerous spindle-shaped cells occur, the extremities of which are more transparent and 

 stain less obviously (Fig. 25, C). Whether there exists any connection between the 

 round eggs and the spindle-shaped cells cannot lie decided, any more than we can follow 

 the further development of the eggs. Full-grown eggs occur sporadically ; they arc 

 large and round, finely granular, with round nucleus. Amongst the ripening eggs 

 there are always found numerous extremely small globules, the significance of which is 

 perfectly unknown to me. Besides the female genital products, numerous spermatozoids 

 occur in the pericardium (Fig. 25, D). 



The cloaca! ducts are not in any way remarkable (Figs. 21-23, or/). They leave 

 the pericardium as wide tubes with ciliated epithelium of irregular height, the inner 

 surface being consequently undulating. First they take a proximal course ; afterwanN 

 they bend and run distally, becoming gradually broader and having a more glandular 

 epithelium, which produces a granular secretion. The state of preservation is imt 

 MI. h as to enable us to decide whether the structure is similar to that <>f 

 other forms, vie., glandular cells, alternating with supporting onea The two ducts 

 unite into a broad praecloacal organ (Fig. 22, /*). Each cloacal duct bears, at 

 the point where it bends proximally, a spacious pouch, placed on a snort stalk, 

 uhi'-h I believe to be a receptaculum seminis ; in both of them numerous 

 spermatozoids occur. 



Now it remains to lc derided to what form this new species, for \v lii.-li I propose 



