86 CALIFORNIA ACADEMY OF SCIENCES. 



very thin, thinner in fact than any other part of the alimentary canal. Of the balance 

 of this canal there is no distinction between oesophagus and sacculated intestine. The 

 gut is every where sacculated, only increasing in thickness towards the genital somites, 

 where it is thickest. The alimentary canal throughout its length is lined by a 

 columnar, ciliated epithelium, outside of which is a very thick vascular layer, with 

 large blood lacunes, directly connected with the dorsal and ventral vessels, which are 

 closely attached to, or almost imbedded in the intestine. The latter as well as the 

 vessels are covered with chloragogic cells, which, especially in the region of the 

 dorsal vessel, are very large (figs. 85 to 91), the layer being thickest close to the 

 strands of mesenteric tissue connecting the intestine with body-wall. 



The free ccelomic lateral vessels in the eight anterior somites are similarly 

 surrounded by a thick mass of glandular cells, arranged around muscular strands, and 

 which are quite distinct from the chloragogic cells and more resemble real glands. 

 Their reaction to stains is entirely distinct from that of the chloragogic cells of the 

 main vessels and of the alimentary canal, staining very deeply with ammoniated 

 hsematoxylon (fig. 84), and showing a coarser grainy secretion, while the real chlora- 

 gogic cells remain much more pellucid aud contain much finer grains. Cells similar 

 to the former are also seen attached to the ccelomic covering of the prostate (fig. 

 107, etc.) They also greatly resemble the glandular cells, or multicellular glands 

 from the pharynx of Pontodrilus and other oligochseta, po.ssessing pharyngeal glands. 



The vascular layer of the intestine is very much developed, especially on the 

 ventral side, where it connects with the ventral vessel, through a thick band of mesen- 

 teric and connective ti.ssue. This as well as the walls of the blood vessels were so 

 thickly studded with a protozoa (Hiiemagregarina) that the structure of the layer 

 could not even in a single instance be properly made out. 



There are no pharyngeal glands, though a few glandular cells are seen scat- 

 tered about between the muscular strands connnecting the pharynx with the body- 

 wall. But these cells resemble more chloragogen cells than true pharyngeal glands. 



The testes are of no unusual structure. The anterior pair, in the specimens I 

 opened, are smaller than the posterior pair, which were always forked, while the ante- 

 rior pair was undivided. 



The ovary in xi is always sigmoid of irregular shape and present the peculiarity 

 that seldom more than one ovum is developed at a time, this one being situated not at 

 the periphery or at the free end of the ovary, but in the inner angle of the sinus. The 

 ovum is unusually small in size and readily detached from the gonad (figs. 78, 108) . 

 It grows large after separation, and is found in numbers in the posterior somites. 



The ooanj is of large size reaching far back to the posterior septum. Its lower 

 end is not only attached to the septum and body-wall, but also to the narrow end of 

 the outer sperm funnel (or ciliated rosette) fig. 96. In one of the specimens sectioned 

 the ovaries either extended past the oviduct through somite xii, or there was a second 

 pair of ovaries in xii. Beddard lias similarly remarked that the ovary in Sutroa is 

 attached to the cells of the spermiducal funnel. 



