M. F. cl'A. Furtado on Viquesnelia atlantica. 251 



made known*. The satisfaction with which I announce new 

 results is qualified by the unpleasant necessity of criticising 

 somewhat harshly the previous researches of Morelet and 

 Drouet on the same subject. It is much to be regretted that 

 these two naturalists, skilled observers and careful writers on 

 other subjects, should have passed by the internal structure of 

 an animal which is, to use their own language, '' sans contre- 

 dit le plus curieux de tous les mollusques A9ordens"t. 



MM. Morelet and Drouet examined the animal of V. atlan- 

 tica without dissection. M. Morelet says : — " Malheureuse- 

 ment, dans le cours du voyage, le petit nombre de specimens 

 que nous avions recueillis s'est egar^, en sorte que je ne puis 

 rien ajouter a la description des formes exterieures que j'ai 

 donn^e plus haut." Only the shell M. Morelet, like a true 

 conchologist, took care not to lose ; and this he describes 

 minutely ; the animal itself, though we are told that the speci- 

 mens were lost on the voyage, is drawn by Lackerbauer as 

 if from nature {^^ ad natyy. 



The descriptions of MM. Morelet:|: and Drouet§ differ nota- 

 bly, which is the more to be wondered at, as these authors 

 conjointly founded the species, and as the memoir of M. 

 Drouet, though later in the date of its publication, was based 

 upon no additional materials : no second visit to the islands had 

 been made ; and the specimens collected during the first visit 

 had, as we are told, been lost. M. Drouet's description comes 

 nearest to nature ; the figure is inaccurate and sketchy. 

 Generic and specific descriptions based upon dissections are 

 now offered to zoologists. 



Fam. Limacidse, Gray. 

 Gen. Viquesnelia, Desh. 



Mantle large, submedian. Tail much compressed. Respi- 

 ratory orifice on the right side, towards the hinder end of the 

 mantle. Caudal mucus-gland absent. Mandible without 

 ridges or teeth, its free edge forming a reentrant right angle. 

 Radula very complicated. Reproductive orifice below and a 



* [StaHle (Moll. terr. du Piemont, p. 121) has proposed to remove 

 V. atlantica to a new genus Plutonia, and this without any knowledge of 

 the anatomy of the animal. — M.] 



t [ V. atlantica is noticed as the most remarkable Gasteropod of the 

 Azores in Dr. H. B. Tristram's observations on the Terrestrial MoUusks 

 of the Azores, contributed to F. D. C. Godman's 'Natural History of the 

 Azores,' p. 107, London, 1870.— M.] 



X [L'Histoire naturelle des Azores, suivie d'une description des Mol- 

 lusques terrestres de cet Archipel : Paris, 1860. — M.] 



§ [Elemens de la Faune A^oreenue : 1861. — M.] 



