Benham. — On New Species of Earthworms. 283 



Dorsal pores are present, at any rate, behind theclitellum ; 

 I see no uephridiopores on the skin, but in section I find 

 them in the lateral gap. 



Internal Anatomy. 



There are four stout septa behind segments 9, 10, 11, and 

 12; those behind segments 6, 7, and 8 are thin and much 

 pouched backwards. 



Vascular System. — The dorsal vessel is double, but united 

 at the septa, as far forwards as the 12th segment. In the 11th 

 the two vessels are bound together in a common envelope, 

 though the canals are separate ; but in the 10th they have 

 united, and the single vessel thus formed continues forwards. 

 The last heart is in the 13th segment. Both this and the 

 heart in the 12th are unconnected with the dorsal vessel ; 

 they are therefore " enteric hearts." being connected probably 

 (for 1 have not examined this point) with a supra-enteric 

 vessel. But the two hearts in 10 and 11 are " lateral hearts," 

 being connected with the dorsal vessel. 



Alimentary System. — The gizzard is large, and occupies 

 segment 6, and pushes back the next three septa. The oeso- 

 phagus remains very narrow, but thick- walled, as it passes 

 backwards to the 19th segment ; there is no enlargement to 

 form a gland. The gut becomes thin-walled in the 20th seg- 

 ment, and dilates to its full size in the next, whence it becomes 

 apparently spiral. 



Excretory System. — The worm is meganephric. 



Reproductive System. — The testes, funnels, ovaries, and 

 oviducts occupy the usual position. There are only two 

 pairs of sperm-sacs, in segments 9 and 12 respectively, the 

 intervening segments being occupied by a mass of loose 

 sperm. The spermiducal glands are thick, convoluted, and 

 confined to their proper segments. The muscular duct is 

 short and narrow. 



There are no penial chaetoe. In segment 18 there are a 

 series of stout muscles, which start from each side of the 

 nerve-cord and pass outwards and upwards to be inserted in 

 the body-wall on the dorsal surface of each side. These 

 " tranverse muscles," as they may be termed, are probably 

 employed during the process of copulation. The effect of 

 contraction, as seen in preserved specimens, is to cause a deep 

 depression of the ventral surface of segments 17 to 19, and at 

 the same time the porophores become more prominent. Such 

 "transverse muscles" are known in other earthworms — e.g., 

 Octochcetus — and their presence seems to be associated with 

 the absence, or, at any rate, small size, of penial chaetae. 



There are two pairs of spermathecse, in the usual seg- 

 ments. The chief part, or "copulatory sac," is relatively large, 



