ORGANS OF NUDIRRANCIIIATA. 347 



Spermatozoa and prostatic secretion, from which it seems Hke^y 

 that the prostata has some influence on the migration of the 

 spermatozoa [see Bruel (6)] ; at any rate it is a fact that the 

 prostatic secretion can mostly be found in at least the first part 

 of the oviduct. In Doto fragilis the secretion was found round 

 the opening of the " funnel " into the oviduct. Notice that in 

 Bcrghia the oviduct opens into the duct between the recejitaculum 

 and the vagina. The prostata is a thick, much-coiled tube ; there 

 is no ductus ejaculatorius, and the penis is simply a thickening 

 of the walls of the male aperture. There are two separate glands 

 attached to the uteru§ ; the smaller one (the albumen gland) does 

 not stain very deeply, and has not such a high epithelium as the 

 second (the slime gland) ; this latter is very voluminous, and 

 is divided into a secretory part and a reservoir which has the 

 form of a tube folded on itself. The two tubes run back on each 

 other from the female opening till past the hindiuost ends of 

 their secretorv lobes, and are in open connection with each other 

 for the wdiole distance.* We have thus a condition similar to 

 that described by Bruel (6) for Caliphylla mcditcrronca, and it is 

 probable that in Bcrghia the eggs pass through the reservoirs 

 of the slime gland on their way to the exterior. 



Tritonia picbcia agrees with Cabna and Dato in having a welb 

 formed, pointed penis, but differs from them and resembles 

 Rhcolia and Bcrghia in having no fertilizing chamber; a very 

 broad part of the oviduct no doubt j^erforms the function of such 

 an organ. The oviduct is very long and coiled, and opens into 

 the anterior end of the albumen gland, through a portion of 

 which the eggs have apparently to pass. The prostata is a very 

 compact, oval organ, and there is a long, coiled ductus ejacula- 

 torius. 



The species studied belong to thi-ee families, of which the 

 Tritoniad?e is generally considered to be the most primitive, the 

 Eolididae intermediate, and the Dotonidse the most highly de- 

 veloped. In all three families the structure of the reproductive 

 organs is very similar, although such a condition could not have 

 been expected, judging by the structural dift'erences in the ex- 

 ternal genital organs. We have in each family a species ( Tri- 

 tonia picbcia, Caliiia Cavolinii, Dot-o fragalis) with a sharply- 

 pointed penis ; we have, in the Eolididse, a species with a pointed 

 penis and others with blunt organs; but this difference does not 

 coincide with any modification of the female organs. True, 

 Caliita Carolina and Doto fragilis combine a pointed penis with 

 a fertilizing chamber, but then Tritonia picbcia has a pointed penis 

 and no such chamber, while Coryphclla riifibranchialis has such 

 a chamber with a blunt penis. We would at least ex])ect to find 



* The dorsal reservoir has no secretory lobes opening into it directly. 

 These lobes lie mostly on the riglit side (penis side) of the animal, and 

 open into the ventral reservoir far forwards ori the left side 



