964 MR. H. R. MEHRA ON TWO NEW INDIAN 



(b) Internal Anatomy. 



The clitelluin is twice as thick as the general epidermis and 

 occupies segments 10 and 11. 



The penial setal sac is large, rounded, about 102 |u in diameter. 

 Its wall is about 30 /z thick and the lumen 42 fx in diameter. In 

 connection with the sac there is a large glandular mass similar in 

 structure to that in A. hashi. The first septum lies between 

 segments 3 and 4. 



The pharynx extends up to the 4th segment, in which the 

 oesophagus begins. The intestine commences in the 9th segment; 

 it is larger till the 20th segment, after which it gradually narrows 

 towards the posterior end, where again it slightly broadens, being 

 stretched by a few muscle fibres, which attach it to the body-wall. 

 The dorsal and ventral blood-vessels are connected by. an 

 undulating commissural vessel in every segment. From the 

 sections I have been able to find the position of heai'ts in 

 segment 8. 



The testes had disappeared, but a large mass of developing 

 sperms fills up the central chamber of the- 9th segment and the 

 sperm-sac as in A. Jcashi. The structure and position of the 

 seminal duct, prostate, atrium and muscular sac agree in essential 

 respects with the desciiption of these organs in A. hasJd. 

 The seminal funnel is cup-shaped with everted lips appearing 

 somewhat like a thistle funnel ; it is attached near the ventral 

 parietes to the anterior face of septum 9/10 and lies in the 9th 

 segment. The columnar epithelial cells lining it are 14-20 /a in 

 height. The yas deferens (text-fig. 9) is short and ITju in 

 diameter, its wall being 6 {^ thick ; its lumen is 5-6 jj in diameter ; 

 it is lined by cubical epithelial cells, which are covered by a thin 

 layer of circular muscle fibres. The atrium is very much like that 

 of the other species, but it is smaller, being 80 ;u by 45"6 ju, in size 

 and lies here in the 10th segment. The cells lining the cavity 

 have lost their cellular appearance owing to the secretion with 

 which they are filled, and are surrounded by a thick muscular 

 sheath. 



The prostate is large and massive ; it extends behind as 

 far as the muscular sac. It is similar in structure to that in 

 A. Jcashi, and opens here also into the antero-ventral border 

 of the atrium. 



The atrial duct (text-fig. 9) is much convoluted ; it consists of 

 proximal and distal portions, and is enclosed by a thick covering 

 of muscle fibres which forms the muscular (coelomic) sac. The 

 atrial duct as it leaves the atrium and before it enters the 

 muscular sac is 23 /x, in diameter. Its lining epithelium consists 

 of cubical cells, outside which there is a thin layer of circular 

 muscle fibres. The proximal portion of the atrial duct is larger 

 and has a wider lumen — about llju, — than in A. hashi. The 

 distal portion of the atrial duct is 31 /x in diameter and is lined 

 by an epithelium, which as in the other species is alternately 



