108 



Shell ; oval, diversely ribbed and reticulated on the outside, the 

 last whorl being somewhat ventricose and often forming a 

 large umbilicus ; columella more or less strongly plaited, 

 ending in a short, sometimes posteriorly recurved canal ; 

 aperture ovate or oblong, with the lip a little expanded and 

 often reticulated. 



This interesting genus so much appreciated by conchologists on account 

 of the many interesting species added to it within the last few years, has 

 elicited a variety of opinion in the determination of its character, and, con- 

 sequently, the place which it should occupy in the system. The shell is 

 mainly distinguished by its having the columella strongly plaited and in 

 never being more than slightly channelled at the base. Linnaeus, and even 

 Cuvier, arranged the Cancellaria on tins account with the Volutes and 

 Mitres ; M. Desliayes, on the other hand, inclines to the opinion that they 

 belong to the family Plicacea, consisting of the genera Pi/ramidella and 

 Tornatella. To the former of these views it is impossible to assent, 

 because the soft parts differ, whilst the plaited columella less strongly de- 

 veloped, appears throughout, to be rather a modification of the same cha- 

 racter in Twrb'mella ; in the latter, it is difficult to understand how such an 

 affinity can exist between animals, whose shells afford so great a contrast in 

 substance and structure as those of Pyramiclella and Cancettaria, the one 

 vitreous and polished, the other distinguished by great variety of highly 

 relieved sculpture, and which seems to indicate the same carnivorous habits 

 as the rest of the Canalifera. The greatest anomaly in the history of the 

 Cancellaria, is that observed by M. Deshayes, of the C. cancellata being a 

 vegetable feeder, and it only remains to be seen whether this is the habit of 

 the genus *. 



The shell referred to this genus by Lamarck, under the name C. 

 citharella, has no plaits on the columella, and will be found to belong to 

 the little group Mangelia, following next in order after Pleurotoma. 



The Cancellarice are not of very common occurrence, and inhabit rather 

 a wide range, they are found at Panama, Peru, China, Eastern Archipelago, 

 &c, and their northern limit is in the Mediterranean. 



* In order to determine the relation of this genus, it is necessary to become further acquainted 

 with the animal ; M. M. Quoy and Gaimard have given a figure of one species, and I have myself 

 had the opportunity of observing another, that which is so abundantly distributed throughout the 

 shores of the Mediterranean. This species differs in some respects from that described by the 

 Zoologists of the ' Astrolabe ', but we are unanimous on the subject of there being no operculum. 

 The animal of C. cancellata crawls upon a disc almost as long as the shell, thin and flattened 

 with the edge slightly truncated and passing a little beyond the head. The head is very large, 

 flat, thin and sharp, forming the segment of a circle at each corner of the extremity of which 

 rises a slim elongated conical tentacle ; the eyes being situated on the outer side of these at the 

 base, where they are slightly projected. I never observed the animal put forth any trunk ; and, 

 having found it invariably on marine plants, am disposed to think it nourishes itself by bruising 

 them with a pair of horny jaws similar to those of other vegetable-feeding mollusks. It is very 



