132 PHILOSOPHICAL TRANSACTIONS. [aNNO 1757- 



lower parts of the corallines, have grown on oysters, which move about here and 

 there, and perhaps serve by way of food for the oyster when it opens. Thus 

 on the 23d of October, 1756, I took an oyster on which grew a large plant of 

 coralline (fig. 15), in which, besides three different species of polypes, I found 

 six different kinds of insects. The first was a worm, (fig. 22.) the head of which 

 was furnished with six larger and two smaller horns. Another was a very small 

 long-legged spider, much resembling the kind called by the French h fancheur, 

 and of very slow motion, (fig. 30.) A third was a worm, as at fig. 27, which I 

 lost while engaged in drawing it. A fourth, fifth, and sixth (fig. 32.) were not 

 visible without a powerful microscope. Of these the animal at letter c is of a 

 wonderful structure. 



Examining* in this manner different oysters and corallines, I saw several 

 more such wonderful insects, the delineations of which are given at figures 26, 

 27, 28, 29, 31. On the 1 6th of the same month of October, several very 

 small corallines were brought me, which had been taken from the surface of a 

 buoy : in these, though often examined with great attention, I could not dis- 

 cover any polypes, but two other very wonderful animals. 



Of these, which the letter a, fig. 23 exhibits, there were thousands, either creep- 

 ing or swimming with an extreme brisk motion : they held or adhered to the small 

 branches of the coralline with their 6 hinder feet, in the manner of the caterpillars 

 called geometrae, sending themselves up and down in a wonderful manner, 

 leaping with great activity from branch to branch. Among these were some 

 few of a larger size, which are represented both in their natural size, and mag- 

 nified, (see fig. 23, b and c.) Another animal, fig. 24, was not less surprizing ; 

 but an idea of all these animals will be better obtained by an inspection of the 

 figure, than from a prolix verbal description. " But if, says Dr. B. " I should 

 " attempt to delineate all the marine animals which I have discovered in dif-: 

 ** ferent corallines, I should undertake a work of infinite labour ; for their num- 

 " ber and diversity are such as to exceed my powers." 



" These observations however may, I hope, prove sufficient to demonstrate 

 ** that corallines are not the work or fabric of polypes, but that they merely 

 " serve as a habitation and refuge, as well as food, to these and a great many 

 \^, pther small marine animals." 



Ejj)lajiation of the plate v.— Fig. 1. shows a plant of coralline called corallina muscosa, sire mtticvs 

 marinus tenui capillo spermophoros. — Fig. 2. Corallina ramulis dichotomis teneris capillaribus rubeuti- 

 bu4. — Fig. 3. A young plant of the corallina tubularia laryngi similis. — Fig. 4. Two species, a, b, 

 (same as fig, land 2), and c. e$chara papyracea utrinque cellulijera, growing to one base, as often 

 happens on buoys. — Fjg. 5. A small branch of red coralline, which I kept for some weeks in^^^y 

 water, often renewed, during which time the small branches a, a, grew very considerably^^nd 

 others, b, b, sprouted forth.— Fig. 6". Part of an oyster-shell, in which, besides certain green fila- 



