342 A HISTORY OF RECENT CRUSTACEA 



The foregoing table has the special advantage of 

 enabling a specimen in almost all cases to be referred to 

 its proper family without dissection. 



It may not be superfluous to remark that tables of this 

 kind are not only dry and fatiguing, but to a great extent 

 useless and unprofitable reading, until the moment comes 

 for practical application. With specimens in hand, and 

 possibly with all the literature relating to the specimens 

 freely at his command, a naturalist may still be bewildered, 

 until he lights upon the page, hitherto dull and unread- 

 able, which briefly states the distinguishing points between 

 several closely allied families or genera. If the characters 

 have been skilfully chosen and clearly and accurately de- 

 scribed, the apparently lifeless record at once becomes 

 luminous and delightful. It will not indeed be available 

 as a specimen of style in a book of elegant extracts, nor 

 should it be selected as a choice morsel for public recita- 

 tion ; it is rather like a bank-note or a cheque, prosaic in 

 expression, but the representative of solid value. 



Family A. Cirolanidce. 



Of the five genera grouped under this heading one 

 may require to be transferred to an independent family. 



Ciroldna, Leach, 1818, has the peduncle of the second 

 antennge five-jointed ; the plate of the second 

 joint of the maxillipeds furnished with hooks ; 

 the first and second pleopods alike, with at least 

 the inner branch submembranaceous ; the uropods 

 with the inner angle of the peduncle produced. 



ConiUra, Leach, 1818, has the same characters, except 

 that the first pleopods are opercular, with both 

 branches hard. 



Eurydice, Leach, 1815, has the peduncle of the second 

 antennae four-jointed ; the plate of the second 

 joint of the maxillipeds without hooks ; the pleo- 

 pods with both branches submembranaceous ; the 

 uropods with the inner angle of the peduncle 

 very little produced. 



