REPRODUCTIVE SYSTEM IN THE SNAIL. 59 



sends a limb (VE] directly to the posterior end of the prostate 

 gland and another (OF) apparently to the duct of the albumen 

 gland (AGD} ; or in other individuals, directly to the convoluted 

 part of the uterus, tangent, but not confluent with the albumen 

 gland duct. Thus in the former case the anterior part of the duct 

 of the albumen gland serves as a common duct (CD} for the pas- 

 sage of both ova and albumen directly into the convoluted part of 

 the uterus at a point near its origin. Even though the two ducts 

 were not confluent and entered the uterus side by side, as some 

 of my material seems to show, and as Baudelot ('63, p. 192, PI. 

 IV.) holds for L. stagnalis and Planorbis corn cits, it would make 

 little or no difference in the time of contact of the ova with the 

 albumen. What effect this albumen has on the movements of 

 sperms in the uterus has not been demonstrated by experimental 

 means. However, masses of sperms enveloped in the albumen of 

 L. s. appressa and L. palitstris eggs are unable to move with suf- 

 ficient freedom to extract their tails from those of other sperms. 

 The entanglement of the sperm tails is apparently not due to 

 normal agglutination, but to chance entanglement during or prior 

 to passage through the oviduct. This observation argues against 

 insemination occurring in the presence of any quantity of albumen. 

 Although Klotz ('89) working on Lyinncea ovatus, with which 

 he found the work of H. Eisig, 1869, on L. auricularia to be in 

 very close agreement, does not bring out the relationship of these 

 ducts definitely; it appears that in his Fig. I the hermaphrodite 

 duct terminates in these two species in a manner quite comparable 

 to that of L. s. appressa. Moquin-Tandon ('55), Cook ('95), 

 Meisenheimer ('21) and Paasch ('43) on L. stagnalis and F. C. 

 Baker ('n) on L. s. appressa do not describe the relation of the 

 parts in this region of the reproductive system. Colton ('12) 

 states that in L. coluniella the albumen gland opens into the her- 

 maphrodite duct before the latter divides to join the male and 

 female conduits. Lacaze-Duthiers ('99) clearly shows that in 

 Ancylis flnviatills the limb of the hermaphrodite duct enters the 

 uterus at a point decidedly anterior to the entrance of the albumen 

 gland duct. 



Much discussion has arisen concerning the structure of the 

 anterior part of the hermaphrodite duct which would enable it to 



