Kew : On the Pairing of Limax maximus. 



253 



are withdrawn that the sperm runs from 

 the groove into the duct of the recepta- 

 culum seminis. The author states, as 

 the ground for this belief, that though 

 the penes examined by him were not 

 severed from the body till the moment 

 the union ceased, the groove was yet 

 full of sperm. In both animals, the 

 receptaculum seminis, which would have 

 received the sperm from the groove had 

 the penis been withdrawn, was empty. 

 Baudelot is supported by Webb, who 

 writes : ' One would say that the use 

 of the penis is to convey the sperm 

 cells to and not into the female orifice, 

 its frill being developed for the purpose 

 of holding them during the act of pass- 

 ing them over to another individual.' 

 According to Laurent, however, this 

 view is unsatisfactory, and the matter 

 is one to which our northern observers 

 — to whose interests 'The Naturalist' is 

 devoted — might usefully give attention. 



It is difficult to form an opinion as 

 to the circumstances under which the 

 remarkable manner of pairing now- 

 described has arisen. The animals' 

 suspension, heads downwards, seems 

 necessary in order that the penes may 

 depend freely and be safe from contact 

 with foreign bodies ; and this can only 

 be accomplished from perpendicular or 

 projecting objects, the faces of walls 

 and rocks, the trunks and branches of 

 trees, etc. It is in places of this kind 

 that Limax maximus usually makes its 

 home; and couples which meet on the 

 ground are observed to ascend to such 

 places before pairing-. Possibly the phe- 

 nomena indicate a former more complete 

 restriction to trees, or to precipitous 

 rocks, such, for instance, as those on 

 which Andrews discovered Gcoma/aciis. 



igoi AugUSt 2. 



Fig. 5.— Genitalia of a large 

 •-lug of the Limax maximus 

 group. After Purkyne, Archiv 

 fur Naturgeschichte, XXV. 

 (1859), PI. VIII.. Fig. 0; pre- 

 sumably diagrammatic in part. 

 A7, genital aperture, the organs 

 above being permanently inter- 

 nal, and that below — the everted 

 penis — external during pairing ; 

 vd and m, vas deferens and 

 retractor muscle, seen through 

 the walls of the penis ; /', op. ping 

 of vas deferens ; .\7>. sperm on out- 

 side of penis; 0, hermaphrodite 

 gland ; a, albumen gland ; oii. ovi- 

 duct ; rs, receptaculum seminis. 



