ISS5.] NEW-ZEALAND EARTHWORMS. 831 



structure of the diverticula, wliicli, as already mentioned, are 

 extremely small, or to compare their structure with that of the main 

 pouch ; but I am able to state, as a fact, that the spermatozoa were 

 contained within the diverticula and not in the pouch. 



The foregoing considerations appear to me to indicate that the 

 diverticula of the copulatory pouches are not merely "diverticula," 

 serving to increase the storage room, but perform some definite 

 function in relation to the spermatozoa, which function is not shared 

 in by the copulatory pouch itself; the very general prevalence of 

 diverticula to the copulatory pouch among Earthworms is an addi- 

 tional piece of evidence that tiiese structures have some importance 

 per se. In some species of Pericheeta these supplementary pouches 

 attain to an extraordinary degree of complication, and are quite 

 divorced from the main co]3ulatory jiouch, o[)ening on to the exterior 

 by separate orifices. In Microclifeta the copulatory pouch itself has 

 apj)arently disappeared ', and only the supplementary pouches 

 remain. Microclueta is therefore at one end of the series, and Lum- 

 bricus, where there are no diverticula at all, at the other. 



I have searched the literature of the subject in order to find out 

 how far the statement that I have just made with regard to the 

 copulatory pouches are in harmony with the observations of other 

 writers. Perrier mentions that in UrochcBtahe never found sperma- 

 tozoa in the copulatory pouches ; but the observation is not of much 

 value, as Perrier himself points out, since the examples of the worm 

 were, without exce})tion, in a condition of incomplete maturity. I 

 can find no other positive statement except in Huxley's 'Anatomy 

 of Invertebrated Animals,' where it is mentioned that the pouches 

 are filled with spermatozoa when copulation takes place. It is 

 possible that this does actually take place even in Acanthoclrilus 

 dissimilis, and that the speimatozoa are rapidly got rid of, and 

 transferred to the diverticula, where they are compacted into masses. 

 This is at any rate in accordance with the facts which I have been 

 able to describe. Dr. Horst* mentions that in PerichcEta sumatrana 

 the diverticula of the copulatory pouches contained "an orange- 

 coloured substance which, highly magnified, appeared to be a mass 

 of spermatozoa." 



In briefly running over the specific characters of the third species 

 treated of in the present paper, viz. A. mxdtiporus, I mentioned tliat 

 the copulatory pouches appeared to be like those of Lumbricus, 

 simple spherical sacs without diverticula. This statement requires 

 some correction ; on making a series of transverse sections through 

 the copulatory pouch and the body-wall in its immediate neigh- 

 bourhood, I detected a number of minute diverticula opening into 

 the duct of the copulatory pouch just before its external aperture, 

 and imbedded in the muscular layers of the body-wall. The diver- 

 ticula, as in the other instances, contained abundant spermatozoa, 

 wiiich were entirely absent from tlie interior of the copulatory pouch 

 itself; the latter contained a granular mass which appeared to be the 



1 Proc. Eoy. Sec. no. 238, 1885, p. \m. 



^ Notes Ironi Leyden Museum, vol. v. p. 190, 



54* 



