yb PKOCKEBINGS OF THE MALACOLOGICAL SOCIETY. 



Javanica, Lara. Java. 



nemorensis, Miiller. Figured by Wiegmann, I.e., pi. ix, figs. 15-22 ; 



pi. X, figs. 1-5; Semper, I.e., pi. iii, fig. 19. Flores. 

 cidaris. Lam. Figured by Wiegmann, pi. ix, figs. 12-14. Rotti. 



Wiegmann states that although the generative organs were 



ineomplete, the five secretory glands were present on the 



amatorial organ. 

 amphidroma, v. Mart. ( = Martini, Pfr.). Sumatra. 

 striata, Gray ( = naninoides, Benson). Figured by Semper, I.e., 



pi. iii, figs. 2la-b. Singapur. 



The following (all from Borneo) are provisionally placed in this 

 genus, but the animals have yet to be examined : — intradentata, 

 God.-Aust. ; regahs, Benson; Bmanensis, God.-Aust. ; Janus, Pfr.; 

 Mindaiensis, Bock ; Moluensis, God.-Aust. 



Malaeologists are frequently led to speculate on the function of 

 accessory glands and cascum-like appendages of the genitalia of the 

 land mollusca, more particularly when they assume the large and 

 striking structure exemplified in the genera Dyahia and Everettia, 

 situated at the distal end of the dart-sae. It seems unlikely that 

 we shall ever know what their true ofiice may be, whether of an 

 excitant sensory nature or some nature unknown to us. Pilsbry 

 calls them the ' coronal glands,' a good term indicating their 

 position with respect to the dart itself. We may assume they are 

 in a measure associated with the beautifully formed calcified darts, 

 because in other eastern genera the amatorial organ is less specialized, 

 the dart more or less soft and muscular, and the organ as a whole of 

 simple cylindrical form. Yet in contradiction to this we are met with 

 the fact that equally elaborately formed ealciferous darts are present 

 in Bamayaiitia, Farmarion, Microparmarion, etc., with accessory 

 coronal glands absent. 



This leads me to allude to another anomalous, inexplicable 

 condition of the generative organs having reference to the dart-sac, 

 viz. that in species of Sitala, Durgella, Taphrospira, etc. The 

 amatorial organ is absent altogether, thus robbing it of much of its 

 iuq)ortance in the reproductive economy, a state of things even more 

 difficult to account for than the presence and use of the complicated 

 coronal glands in the genera I have mentioned.^ 



EXPLANATION OF PLATE X. 

 Figs. I-XIV. Byakia striata, var. 

 B. amatorial or,^an ; D.gld. gland of amatorial organ ; ov. ovar}' ; P. penis ; 

 r.m.P. retractor muscle of penis ; sp. spermatheca ; ttt. uterus ; v.d. vas deferens. 



While writing this paper the October part (vol. xi, No. 8) of the Journal of 

 Coiichology has come to hand, which contains a list of the sinistral shells in 

 the Manchester Museum by Mr. E. Standen. I notice the genus Ariophanta 

 is still made the receptacle for animals differing most widely from each other. 

 Mr. Standen has evidently not seen what has been published by myself in 1891, 

 and later by Professor Wiegmann in 1898. In this list only Icevipes (the type), 

 fiivcata, fhijn'Hs, and Bajadera represent the genus Ariophanta. 



