95 



a iid orange- yellow, dlfpofed in minute confluent fpecks ; 

 tiiis however is fubje6l to vary in fhade, in different fpe- 

 cimens, as well as in different parts of the lame individual : 

 in the middle of the anterior fliield are two fmall black eyes, 

 placed remote, and funk in fmall cavities of a pale colour : 

 \\\e fujlentacuhun is very large, and extends behind and on 

 the fides into broad fin-like membranes, which refle<5l and 

 almofl conceal the fliell ; the two lateral ones turn under the 

 fliield at their anterior edges ; the pofterior membrane is 

 divided from the others by a deep finuofity, the right fide is 

 fpread on the place whereon it is crawling ; the left fide 

 takes a turn round the pofterior end of the Ihell, and reflefts 

 over it. "When the edge of the fliield is thrown up, and ex- 

 pofes the longitudinal divifion that feparates that part from 

 the fujientaculum, a yellow marking in elegant ramifications 

 hke a feather, is obvious on each fide, but not detached a» 

 in the animal of Bulla plumula, 



A few mutilated fpecimens of extraordinary fize, origi- 

 nally found in the efiuary of Kingjhridge, left no doubt of 

 its inhabiting fome part of that inlet; but fo local are 

 fome of the produ6tions of nature, that not till after five 

 years repeated fearch, did we difcover the bed or place of 

 refort, and where an abundance may generally be found at 

 the lowefl ebb of a fpring tide. On tlie fouth fide of a fmall 

 ifle, ufually known by the name of the Salt Stone, by far the 

 fineft fpecimens we have ever feen may be colle6led ; fome 

 of which are an inch and a quarter in length, and invariably 

 covered with a ferrugenous epidermis. 



FONTINALIS. 



