968 NOTES ON AUSTRALIAN EARTHWORMS, 



in xii have nothing of this kind behind them and I was able to see 

 the vasa deferentia passing through the mesentery to which they 

 were attached. There is a pair of much incised prostates occupying 

 nearly three segments, xvn to xix ; the genital ducts which are 

 sickle-shaped and are joined by the distal portions of the vasa 

 deferentia close up to the gland, do not open directly on to the 

 exterior but each on the summit of an elliptical elevation, possibly 

 a sac, nearly as long as the prostate. The whole arrangement is 

 very similar to that figured by Vaillant in P. cingulata (1) with 

 this difference, that in the Darnley Island worm both prostates 

 and genital ducts are relatively longer, and the vasa deferentia join 

 the prostatic ducts closer to the glands. I hope to give a figure of 

 these structures later on. 



The two ovaries occupy the usual position in xiii ; the arrange- 

 ments of the oviducts I was unable to follow ; there are four pairs 

 of spermathecse in segments vi to ix ; each spermatheca consists 

 of a principal pouch and of a caecum ; the former is divided by 

 a constriction into a relatively broad proximal portion or stalk, 

 and a slightly broader nearly cylindrical or depressed distal 

 portion, the whole somewhat pear-shaped ; the caecum is long 

 and narrow, irregularly knobbed or provided with rudimentary 

 blunt processes, of a glistening red colour contrasting with the 

 white pouch, and comes off from the basal portion some distance 

 below the constriction. 



In front of the gizzard there are four complete mesenteries ; the 

 first one behind is very thick, the next three are also thick, but 

 after those they are quite thin ; the thick ones are all concave 

 forwards like saucers, but are not in contact. 



There are four pairs of transverse hearts in x to xiii, of which 

 all but the first pair are very large ; in some of these segments 

 there is a second longitudinal vessel from which some of the hearts 

 arise. 



In segments vand vi tuftsof glandular tubules seemingly attached 

 to the posterior mesenteries are especially noticeable ; they are 

 perhaps salivary organs. Segmental organs not at all conspicuous. 



(1) Ann. Sci. Nat. Zool. (5), Vol. x, pi. x, fig. 7. 



