498 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXIV. 



Internal anatomy. — The worms being too small for dissection, the inter- 

 nal anatomy was determined by examining the worms while in Cedanvood oil 

 when it is nearly transparent and the rest of the anatomy was made out 

 from vertical longitudinal, horizontal longitudinal, and transverse sections. 

 The sections were either stained with Delafield's hsematoxylin or with 

 Heidenhain's iron-hsematoxylin followed by Eosin. 



First definite septum is J, Septa ^ and | are thickened. 



Alimentary canal. — The mouth is overhung by the ^?"osiommTO, and leads 

 into the buccal cavity which extends through the first three segments. The 

 buccal cavity is followed by the pharynx which has a rather thick muscular 

 wall and the upper surface of it is covered over by a large mass of glandular 

 tissue, the septa extend into this tissue and cut it up according to the 

 segments in which it lies. The pharynx finishes in the sixth or in some 

 cases in the seventh segment whence the oesophagus begins. The oesophagus 

 is a straight tube extending up to the fourteenth segment. Only two pairs 

 of calciferous glands are to be seen lying in segments xi and xii, the one in 

 segment xi being really a pouch in the side wall of the oesophagus, 

 but the opening of the gland in the xii segment into the oesophagus could 

 not be seen, it merely appeared as a thickening in xii segment showing in 

 sections the characteristic lamellated appearance of the calcareous glands, 

 nor was the opening of this into the anterior one to be made out. The crop 

 which follows is a thin walled dilatation of the alimentary canal lying in 

 segments xiv and xv. The Gizzard lies in segments xvi and xvii. Its wall 

 consists of the following layers : — 



1. Outermost is a single layer of longitudinal Tnuscular fibres. 



2. Many layers of circular muscular fibres come next. 



3. A layer of columnar epithelial cells is next seen in some places 

 between the bases of the epithelial cells small rounded cells are also seen 

 filling up the gaps. This layer secretes the chitinous lining of the gizzard. 



Behind the seventeenth segment the intestine extends as a wide thin 

 walled sacculated tube up to the anus ; the intestine in some cases was seen 

 to push the septum i-^ forwards on the sides of the gizzard. The 

 intestine is constricted intersegmentally owing to the septa while sacculated 

 in the segments. In the first four or five segments the intestine in the 

 intersegmental, regions sends out villus-like projections, which may branch ; 

 this appears to be a contrivance for increasing the absorptive surface of the 

 intestine. The typhlosole becomes well marked after segment xix and in 

 transverse sections appears as a deep ridge projecting into the cavity of the 

 intestine. 



There are five pairs of hearts in segments vii — xi, the ones in 

 segment v being rather small ones. 



Nephridia. — are of the meganephric type, they are arranged in pairs on each 

 side of the intestine except for the first five segments and the last few 

 in which they are absent. 



The reproductive organs are lodged in segments xi — xv. 



Male organs. — The two pairs of testes lie in segments xi and xii free and 

 not enclosed in the testicle sacs. The seminal funnels also lie in segment 

 xi and xii. There are only two pairs of seminal vesicles depending from 

 the septa 1= and li and lying in the segments xi and xii. 



Female organs. — A pair of ovaries and the oviducal funnels lie in the xiii 

 segments, the oviduct pierces the septum if ^aiid opens on each side on 

 the xiv segment. 



Spermathecse absent. 



Cocoon formation was observed in one specimen, when found, the 

 cocoon was seen as a raised projection of the clitellum already formed all 

 round the clitellum as a cylinder-like covering, after about two minutes 



