OF THE LIVING CLIO CAUDATA. 187 



alone warrants the whole of the Pteropoda to be included under the term Cepha- 

 lophora. 



The ease with which naturalists interchange names without any conciliatory 

 explanation, is certainly a great stumbling-block to the beginner. Thus, if he 

 were to fall in with Clio caudata, as I have done, and immediately consult all 

 the authorities within his reach, in some modern work he may find a figure of the 

 creature he is in quest of, though denominated Clio australis, but on still further 

 inquiry as to the authorship of that figure, he discovers that it is a lineal de- 

 scendant of a figure of Clio a longue queue, given in the " Voyage de la Bonite." 

 Now, on comparing this with De Blainville's figure of Clio australis, he may 

 probably perceive even generic differences between them ; but, continuing his 

 search, he looks over one or two other modern books, and one can scarcely say 

 whether his mind is settled, or his confusion is made still greater, to encounter 

 stereotype repetitions of the figure of the said Clio australis of De Blainville 

 boldly named Clio horealis. 



If there is indeed such an animal as Clio australis, and M. De Blainville's 

 figure is a correct representation of it, it is obvious enough that the species 

 horealis and australis are members of the same genus ; but as both differ so re- 

 markably from the so-called C. caudata, and the broad trigonal-tailed species, of 

 which I have given a short notice and figure, it strikes me that there are ample 

 grounds for the establishment of a new genus, to receive, at least, the two last- 

 mentioned species, while at the same time it will become apparent how little the 

 nature of the respiratory system can be depended upon for generic characters, 

 though it may be of great specific value. 



Not desiring to add unnecessary names to a list already large, I merely sub- 

 mit the views above expressed to the consideration of zoologists, who may form 

 their own judgment on the matter. The more important characters are simply 

 as follows : — 



Tentacula, two, minute, on either side of the head anteriorly; Cephalic arms. 

 four, perfectly retractile, long, and conical, with sucker points still more rudi- 

 I mentary than those in Clio ; Proboscis exsertile, broad, depressed, and pointed 

 in front ; Oi'al aperture, superior, oval, with minute lower lip uncini ; Cheek 

 pouches shallow, but evertile, and furnished with curved conical teeth ; Lingual 

 pavement broad, with a median series. 



Setting the above characters aside, however, the original object of the paper 



i has been to show the great importance of the study of all soft, collapsible, and 



contractile animals in the living and expanded state ; for I am much of opinion. 



' that the Northern Clio, examined in this way, will be found to present very similar 



characters, or such as could not be arrived at by the most patient dissection of 



spirit-preserved specimens. 



