308 PHILOSOPHICAL TRANSACTIONS. [aNNO 1758. 



about in a spiral manner; l6 tentacula or claws; 6 of the hinder ones on each 

 side cheliferous. This account differing from that given by the ingenious Mr. 

 Needham, in his Microscopical Essays, Mr. E. gives the character of this ani- 

 mal, as it appeared from many observations made on it, while alive in salt water; 

 and these he compared not only with many dried specimens of other varieties, 

 but likewise with some that were preserved in spirits; and he found that the 

 parts of the animal agree in all the species. 



The experiments that he made, were on the common English barnacle, viewed 

 by a microscope, which is very frequently met with, in the winter, on oysters 

 and other shell-fish. This animal has 24 claws, or cirrhi (fig. a, pi. 11) which 

 are disposed in the following manner: the 12 longest stand erect, rising from the 

 back part of the animal; they are all joined in pairs near the bottom, and in- 

 serted in one common base. These appear like so many yellow curled feathers; 

 they are clear, horny, and articulated. Every joint is furnished with 2 rows of 

 hairs on the concave side. The animal, in order to catch its prey, is continually 

 extending and contracting these arched hairy claws, which serve it for a net. 

 The 12 smallest claws are placed next to these, 6 on each side: these are divided 

 into pairs; that is, 2 claws to one stem, like the chelae or claws of the crab. 

 These are more pliable, and fuller of hairs, than the others, and seem to do the 

 ofHce of hands for the animal. The whole number of claws lessen in size gra- 

 dually each way, from the tallest in the back, to the last but one of each side 

 in the front; which last 2 are of the middle size. 



The proboscis or trunk rises from the middle of the base of the larger claws, 

 and is longer than any of them : this the animal moves about in any direction 

 with great agility : it is of a tubular figure, transparent, composed of rings lessen- 

 ing gradually to the extremity, where it is surrounded with a circle of small 

 bristles, which likewise are moveable at the will of the animal. These, with 

 other small hairs on the trunk, disappear when it dies. Along the inside of 

 this transparent proboscis the spiral dark-coloured tongue appears very plain : 

 this the animal contracts and extends at pleasure. 



The mouth appears like that of a contracted purse, and is placed in front, 

 between the fore claws. In the folds of this membranous substance are 6 or 8 

 homy laminae or teeth standing erect, each having a tendon proper to direct its 

 motion. Some of these teeth are serrated, others have tufts of sharp hairs in- 

 stead of indentations on the convex side, that point down into the mouth ; so 

 that no animalcule that becomes their prey can escape back. Under the mouth 

 lie the stomach, intestines, and the tendons by which they adhere to the shell. 

 This then is the general character of the animal of the whole genus, whether 

 with stems or without. 



Mr. E. next gives a short description of the several kinds he had met with. 



