ON BENHAMIA CQECIFERA, N. SP. 109 



InBenharaia coecifera the dorsal vessel gives origin to 

 four pairs of very large hearts, lying in Segments ix, x, xi, xii. 

 These may be, and I suspect are, connected also with a supra- 

 intestinal trunk, as Horst has described in certain species of 

 this genus ; but I could not, without injury to the worm, 

 determine the point. 



In Segments vii and viii two other pairs of hearts arise ; 

 these are smaller, and differ in their appearance from the 

 posterior pair, being more irregular in their swellings. The 

 large posterior hearts remain greatly distended till close to the 

 ventral trunk, to which they are joined by a short narrow 

 vessel (fig. 8). The heart in Segment viii has a less diameter 

 and a longer, narrow vessel connecting it with the ventral 

 trunk. The heart in Segment vii is much shorter. About 

 midway between the dorsal and ventral trunks it suddenly 

 narrows ; this narrow part opens into a small spherical dilata- 

 tion, whence arise two delicate vessels ; one goes forwards to 

 the side of the second gizzard, the other continues downwards 

 to enter the ventral vessel. This anterior heart recalls most 

 curiously the condition of the heart in Segment ix of Megas- 

 colex figured by A. G. Bourne (loc. cit. pi. 8, fig. 4). 



The dorsal vessel terminates here in Segment vii 

 after giving rise to the hearts (figs. 7, 8), but its place appears 

 to be taken by a pair of " latero-longitudinal " vessels (I use 

 this term topographically, and with no implication as to their 

 homology with those so named by Bourne in Moniligaster). 

 These (/. /. v.) arise, as far as I could determine, as branches 

 of the dorsal trunk just in front of the third pair of hearts, 

 i. e. in Segment ix, and each runs forwards to the pharynx, 

 giving off vessels to the gizzard and other structures. 



The blood-vessels on the body-wall present a feature which I 

 have not seen noticed in any previous account. In each seg- 

 ment there is a small vessel having a circular direction along 

 the inner face of the body-wall. I do not know its relation to 

 the main trunks, but, as it is readily recognisable with the 

 naked eye : on each side of its course, it gives rise to a fairly 

 regular series of small globular dilatations ; these were more 



