196 BUNODID.E. 



the yellow mark is broader and near the mouth ; in the others, it is more 

 slender, longer, and reaches to the tentacular region. 



Tentacles. Pellucid grey, with the front 

 face olive, on which are scattered numerous 

 spots of opaque white : these spots are gene- 

 rally roundish, or polyhedral, and large and 

 tentacle small ones are crowded together. 



{lateral view). Mouth. Blackish, with the gonidial tuber- 



cles of a more intense hue. 



Size. 



Button an inch and a quarter in diameter, elongating to a height of 

 two inches ; expanse of flower two inches. 



Locality. 

 Both sides of the Bristol Channel ; rocks within tide-marks. 



Varieties. 



a. Hygroxyla. The green condition described above. 



j3. Xeroxyla. Column dingy brown, with slightly darker warts ; disk 

 of the same tint ; marked as in o. 



y. Caustoxyla. Column reddish chocolate, with darker warts ; disk dark 

 olive ; marked as in a ; the central half sometimes white. 



I first discovered this species at Lidstep, on the coast of 

 Pembroke, in 1854, and described and figured it in " Tenby ; 

 a Seaside Holiday." Very little has been added to its 

 recorded history since that time ; not more than four speci- 

 mens having occurred, so far as I am aware, to subsequent 

 researches, all of which were obtained near Ilfracombe. 



Though manifestly a rare species, I was so fortunate as 

 to light upon a numerous colony at its discovery. About 

 a dozen individuals of different sizes were associated in the 

 dark angles and pools of a little insular rock exposed at 

 spring-tide, that lies just off the cove called the Droch, 

 near Lidstep. They were not troglodyte in habit, but 

 adherent to the open rock, and therefore easily detached. 

 The species seems social ; clustering together in groups, 

 mutually pressing each other's sides. 



The habits of the Glaucous Pimplet in captivity are 



