Dr. Cantor on Indian Fish producing Isinglass, 399 



Cyclas cornea, Linn. Common. 



Cyclas calyculata, Drap. The only locality I know for this shell 

 in the district is in a marl pit near Hutton Grange. 



Pisidium obtusale, Pf. Common on the Weald Moors. 



Pisidium pnsillum, Jen. I have at different times taken two or three 

 specimens of this shell on the Weald Moors. 



Pisidium nitidum, Jen. Not very uncommon on the Weald Moors. 



Pisidium ammeum, Mull. Taken in the same locality with the last. 



XLIX. — On the production of Isinglass from Indian Fishes, 

 By Dr. Cantor, Corresponding Member of the Zoological 

 Society*. 

 In the December Number, 1838, of Parbury's Oriental Herald 

 appears a letter ' On the Suleah Fish of Bengal, and the Isinglass it 

 affords' : the description of this fish I shall quote in the words of 

 the anonymous writer. " The Suleah Fish," he observes, ** when at 

 its full size, runs about four feet in length, and is squaliform, resem- 

 bling the Shark species in appearance, but exhibiting a more delicate 

 structure than the latter. The meat of this fish is exceedingly 

 coarse, and is converted by the natives, when salted and spiced, into 

 * burtah,' a piquant relish, well known at the breakfast-tables of 

 Bengal. The bladder of the Suleah may be considered the most 

 valuable part of it, which, when exposed to the sun and suffered to 

 dry, becomes purely pellucid, and so hard that it will repel the edge 

 of a sharp knife when applied to it. These bladders vary from half 

 a pound to three quarters of a pound avoirdupois in weight, when 

 perfectly dry. . . . The Suleah Fish abounds in Channel Creek, off 

 Saugor, and in the ostia or mouths of all the rivers which intersect 

 the Sunderbuns, and are exceedingly plentiful at certain seasons.'* 

 Conceiving the great importance of the discovery of isinglass 

 being a product of India, I was naturally anxious to examine the 

 source, arising from a branch of natural history to which in particular 

 I have devoted my attention ; but from the general nature of the de- 

 scription, I was obliged to defer my desire of identifying the fish till 

 some future opportunity should enable me to do so. Quite unex- 

 pectedly, however, a few days ago, the last overland despatch brought 

 me a letter from my valued friend Mr. McClelland, a Corresponding 

 Member of this Society, an extract of which, bearing upon the point 

 in question, I lose no time in laying before the Society : — ' .... I 

 have now to mention what is of far greater importance in another 



« Read before the Zoological Society, July 23, 1839. 



