208 M. E. Perrier on the Organization of 



this course. Those now in question belong to a genus esta- 

 blished by Schmarda, of which two species have recently been 

 investigated by M. L^on Vaillant, but iipon preserved speci- 

 mens. Some important details which we have been fortunate 

 enough to bring to light, allow a more exact account to be 

 given of the organization and affinities of these worms, and to 

 extend the results already obtained to Lumbricina belonging 

 to other genera. 



We shall especially notice here the woi-m from Calcutta, 

 reserving the few differences presented by that from the West 

 Indies for the memoir which we shall publish on this subject. 



The worm in question is from 140-150 millims. (about 

 5\-Q inches) in length, and about 3 miUims. (or ^ inch) in 

 diameter. Its body contains about 106 segments, not inclu- 

 ding the head. Each segment bears in its middle a girdle of 

 from forty-five to fifty isolated setee, placed at equal distances 

 apart and arranged in a circle. On the head we see a slight 

 prominence, slightly notched in front ; the clitellum appears 

 after the thirteenth segment, and occupies tlie space of three 

 segments, which is easily ascertained either by means of the 

 nervous ganglia or by means of the girdles of setae, which 

 often persist after the formation of the clitellum. The seg- 

 ment which follows the clitellum is therefore the seventeenth ; 

 and it is in the lower surface of the eighteenth that the two 

 male genital orifices are seen. The fourteenth segment, or 

 the first of the clitellum, bears in the middle of its lower sur- 

 face, but quite in front, a single orifice, which we regard as 

 the female orifice. At the point of junction of segments 6 & 

 7, 7 & 8, and 8 & 9, other orifices are seen on each side of the 

 lower surface ; these are the capsuligenous glands of D'Ude- 

 kem, the copulatory pouches of more recent authors. 



The digestive apparatus is very complex. It consists of a 

 pharynx with thick and glandular walls, of an oesophagus 

 occupying the sixth, seventh, eighth, and ninth segments, of 

 a muscular gizzard occupying the tenth segment, and, lastly, 

 of an intestine analogous to that of the Lumhrici. 



The walls of the pharynx are covered with glands of two 

 kinds — the upper ones formed by two rolled-up tubes united 

 by an intermediate substance, the lower ones containing sphe- 

 rical granular cseca. These glands open into the pharynx by 

 three pairs of orifices. 



Into the oesophagus there open : — 



1. Three groups of glands, supported upon the partitions 

 which separate the fifth segment from the sixth, the sixth 

 from the seventh, and the seventh from the eighth ; these 

 glands are formed by isolated floating tubes, bent into loops, 



