THE OLIGOCH^TA TERRICOL^. PART I. 199 



sence of septum IX/X, a condition which is precisely the reverse 

 of that which obtains in most other species of the genus. I quite 

 agree with him that septum VIII/IX is present; it was very 

 obvious to me, although thin and delicate. I found, also, the 

 septum lying between segments IX/X, which would be much less 

 easily missed than the preceding, for it is much thicker than that 

 which divides segments VIII/IX. It is to be remarked that in 

 the present species, if it be a species, the 3 septa in front of 

 the gizzard are much thicker than the slightly increased ones 

 which follow the gizzard. 



The intestinal cseca of the species P. posthuma appear to vary, 

 being larger or smaller or even absent. It may be that here 

 we really have a character which will separate true P. posthuma 

 from those forms to which I have proposed here to give a new 

 name; for in the individuals upon which I report in the present 

 communication the cseca were small; finger-shaped, that is, not 

 dwindling at the free extremity; and white, instead of brown 

 like the intestine which is generally the case. The last pair of 

 hearts is in segment XII. 



The position and nature of the testicular sacs are known in 

 Pheretima posthumaJ^ In the examples which I refer to an 

 allied species here, these sacs were 2 pairs and in segments X, 

 XI, as' usual. The anterior pair of sacs, however, was very 

 markedly smaller than the posterior pair and the 2 sacs on each 

 side of the body were in close contact. Indeed, in the specimen 

 dissected, the sac of the Xth segment on the left side was dis- 

 tinctly smaller than its fellow of the right side of the body. 

 The testicular sacs of segment XI were very large. There were 

 clearly 2 pairs of sperm-duct funnels. The sperm sacs, as in 

 typical P. posthuma, were in segments XI and XII. The sperm- 

 iducal glands of P. posthuma are spoken of as small ("Prostaten 

 mit ziemlich kleinen Driisentheil." Michaelsen). Those of the 

 species now under consideration can not be so described, due 

 regard being had to the slender build of the worms themselves. 

 Each gland extended through quite 4 segments and this was the 

 case in 2 individuals which I dissected. On the other hand, the 

 duct seems to be, not unlike that of P. posthuma, but at the same 

 time it may present differences. It is curved and S-shaped 

 where it issues from the gland and until it makes a bend upon 

 itself and runs directly backward toward the gland to open to 

 the exterior without the intermediary of a bursa copulatrix. 



" See Cognetti di Martiis, Boll. Mus. Zool. Torino (1909), 24, No. 602. 



