PINNOTHERES, Oil PEA-CRABS. S3 



Body bright yellow, with a few black bristles above ; head round 

 the eyes and beneath white ; mouth pale yellow, clothed with 

 white hairs ; antennae bright yellow ; thorax with three slender 

 pale brown hardly seen stripes above and a lemon-colour stripe 

 on each side ; metathorax black, shining ; abdomen clothed with 

 black hairs ; telum rust colour ; legs yellow, clothed with black 

 hairs ; wings limpid, slightly yellow at the base, with two large 

 black spots, one nearly square, joining the middle of the costa, 

 the other at the tip ; the female has a third narrower spot joining 

 the upper border before the tip of the wing ; nervures yellow ; 

 poisers bright lemon colour. (Length of body 1| — 1| line ; of 

 wings 3j — 3| lines.) 



May and June ; on grass in meadows ; near London. 



Art. VI. — Memoir on the Metamorphosis and Natural His- 

 tory of the Pinnotheres, or Pea-Crabs. By W. Thompson, 

 F.L.S. 



If we were to search out an instance amongst the Crus- 

 tacea, best calculated to exemplify the employment of deep 

 design, and admirable adaptation of an animal to the mode of 

 life it was intended for by its benevolent Creator, I think we 

 should find it in the Pinnotheres. No person who reads this 

 memoir with attention, but must be convinced of these obvious 

 truths, or insensible to the operation of a providence, which 

 caters for the most insignificant creature with as much care 

 as for man himself, and which shows the Supreme in his attri- 

 butes of omniscience and omnipotence, here, as at every step 

 we take in our investigations into the ample book of nature. 



The species of this curious and highly interesting genus of 

 crabs, of which the type is Cancer pisum, Linn, the Pinno- 

 theres pisum of Latreille, &c, are exclusively parasitic, but 

 unlike the more familiarly known hermit-crabs, which take up 

 their residence in empty univalve shells, these find their way 

 into the tenements of living bivalves, which the females never 

 afterwards quit ; there they remain, feed, grow, receive the 

 visits of the males, and breed. How wonderfully they are 

 adapted to this mode of life is obvious on the slightest in- 

 spection : their small size, rounded form, without angles or 

 projecting spines, the softness and yielding nature of their shell, 



