GO CAMI'lHtMA ACADK.MV Ol' SCIENCES. 



in somites v, vi, vii and viii, again to assume a more tubular form in ix. In the pos- 

 terior part of this somite it is joined by tlie two diverticula. The tul)u]ar intestine 

 proper occupies the two somites x and xi. In xii begins the sacculated intestine. The 

 diverticula of the oesophagus are very long, narrow and slender, more so than in any 

 species of Ocuerodrilus which f have seen. These exterior features offer nothing 

 peculiar. Tiie lateral blood vessels issue, as usual, from the anterior points of the 

 diverticula. 



These diverticula of tliq oesophagus originate in the j)Osterior part of the 

 somite, and not in the anterior part as in Kerria. The structure of these diverticula 

 corresponds with that of the same organ in Ocnerodrilus. Only in that genus the 

 rule a2>pears to be that tiie interior of the diverticiilnni consists of one single chamber 

 encroached on by a few parallel ridges. Tlie diverticulum of P/m uicodrUuri tnxti' is 

 in the central part four to eight chambered, divided off longitudinally, presenting the 

 same appearance as an orange when cut through crosswise (figs. 14-16). The number 

 of chambers varies, as in one specimen I found the right hand diverticulum to have 

 four chambers, while the left one had five chambers. In sections near to either end 

 these chambers fuse further and finally only two and one chambers are left. 



But this fusion is unequal at the two respective ends. In the end nearest the 

 junction witb the alimentary canal there is only one chamber found, and a little 

 further forward there are two chambers, the number increasing until generally eight 

 chambers are found in the center. From there on no increase is made, but the cham- 

 bers decrease in width, and at the anterior end suddenly fuse into one which is small 

 and narrow, not thicker than a blood vessel. The longitudinal blood vesssels are very 

 much the same as in Ocnerodrilus, but generally more in number. 



The number of blood vessels in each diverticulum varies with the place where 

 located in the diverticulum. The section nearest to the posterior septum of the ali- 

 mentary canal shows the two laterals from the dorsal vessel entering the diverticula. 

 To begin with, they are seen on the outside of the cellular mass of the diverticulum, 

 while in succeeding sections they appear like a few blood vessels scattered on the out- 

 side of the e|)itlielial cells. In succeeding sections these vessels are seen to increase 

 in number until in the center of the diverticulum they number about one hundred. 



The blood supply for these organs come from branches of the dorsal vessel and 

 not from collective vessels from the alimentary canal. 



Salivnrij (jlands are as usual found attached to the muscles of the pharynx, Imt 

 they are smaller and less numerous than in Ocnerodrilus, the pharynx being less 

 lobed and more compact than in that genus. These glands open through ducts, which 

 follow muscular strands into the pharyngeal cavity in a similar way as will lie more 

 in detail described in Pontodrilus. In fact it is probable that all the suprapliniyngeal 

 glands in the respective genera of Lumbricids open similarly and without any great 

 variation as to detail (fig. 1<S). Tlu' narrow ducts from tiie gland penetrate the pha- 

 ryngeal epithelium and form at its outer edge small ovoid po(d<els for temporarily 

 storing a small amount of the salivary secretion. These ducts end with the pharynx. 



