Smith. — Notes on New Zealand Earthworms. 131 



conspicuous penial setae, but it appeared to me that one or 

 two of the setae in the immediate neighbourhood of the genital 

 pore were rather longer than the others. The ovary is in 

 segment xiii., and the oviduct opens into the same segment ; 

 there is nothing unusual about either of these organs. The 

 ovary, as in most earthworms, is not a compact organ, but is 

 prolonged into numerous filiform processes. The egg-sacs 

 (receptacula ovorum) are very conspicuous structures; they 

 lie upon the posterior surface of the septum separating seg- 

 ments xiii. and xiv., and on either side of the intestine. 

 These organs are larger than is generally the case, and have a 

 racemose appearance ; in both these points they present an 

 interesting resemblance to sperm-sacs ; furthermore, they con- 

 tain numerous gregarines. In one specimen, the genital region 

 of which I investigated by transverse sections, the structure 

 of the egg-sacs was a little different from that of other earth- 

 worms which I have had the opportunity of studying. The 

 walls are tolerably thick, and appear to be made up of fibres. 

 Interspersed among them are nuclei which are extraordinarily 

 numerous ; the blood-supply was not very great, but this may 

 be due to accidental causes. The presence of egg-sacs in 

 Perichceta has been noted in but four species. In P. intermedia 

 the egg-sacs were filled with mature ova, all of which were 

 surrounded with a perfectly distinct follicular epitheliuin com- 

 posed of flattened nucleated cells. In addition to this follicular 

 epithelium — between which and the ovum is a distinct vitelline 

 membrane — many of the ova were also furnished with a small 

 number (four or five) of germinal cells attached to one pole. This 

 is an interesting resemblance to certain of the lower Oligochcsta, 

 in the majority of which the ova are detached from the ovary, 

 and fall into the egg-sacs in company with a munber of 

 germinal cells, which probably serve for the nutrition of the 

 ovum. There are four pairs of spermathecce, occupying seg- 

 ments v.-viii. ; each is furnished with a single supplementary 

 pouch of small size : this was conspicuous by reason of its yellow 

 colour, and, as in P. sumatrana, was crowded with spermatozoa. 

 The septum to which the egg- sacs are attached is one of the 

 specially-thickened septa, of which there are six, dividing seg- 

 ments viii.-xv. The egg-sacs are attached close to the 

 oesophagus, and where the oesophagus perforates the septum 

 there is a space left, through which the egg-sac is prolonged, 

 opening into the interior of the thirteenth segment, and coming 

 into very close relations with the funnel of the oviduct ; the 

 passage of the ova into the egg-sac is facilitated by this, and 

 by the fact that the two thick mesenteries which bound seg- 

 ment viii. are closely approximated, so that the actual cavity 

 of the segment is much reduced. The part of the egg-sac 

 nearest to its attachment forms a spacious cavity, undivided 



