VOL. LII.] PHILOSOPHICAL TRANSACTIONS, 529 



and Newland, where it is thrown up by the sea*, inclosed in a large hollow root 

 of the fucus palmatus. 



The 3d species, is the hydra disciflora, tentaculis retractilibus subdiaphanis ; 

 corpore cylindrico, niiliaribus glandulis longitudinaliter striate* Its body when 

 extended, is of a cylindrical figure, and constantly marked with some rows of 

 small knots, or glandulae, that are placed in straight lines from the top to the 

 basis of this cylindrical stalk. Each row is composed of 3 files of glandulae, of 

 which the middle one is remarkably larger than the two others ; their number 

 is uncertain, yet he never met with less than 8 rows in an animal grown to its 

 full age. The colour of the stock near its basis is a pale red, and the rest is of 

 a yellow, mixed with a grey ash-colour. The glandulae are almost of the same 

 colour with the body, except those of the middle file of each row, which is 

 white. Out of the top part, or the disk of the polype, grow the feelers, from 

 18 to 36 in number; they are of a half-transparent substance, and of a whitish 

 colour, variegated only at the upper part of the feeler, like the back of some 

 snakes, with several cross-lines, and brown spots of an irregular figure. The 

 disk of this polype is always convex, and chiefly of an orange colour, except to - 

 wards its periphery, which is marked with many dark brown spots, that sur- 

 round the insertion of the feelers. At the least irritation, this animal con- 

 tracts its body, and changes its cylindrical figure into a conoidal one. The fis- 

 sures of the rocks in the sea are the only place where he met with this sort of 

 polypes, which is not common on the coasts of Cornwall. 



Of this species he found two varieties. The top parts of the one are in shape 

 and colour much the same with those of the already described animal ; the stalk 

 only is of a deep green colour. The 2d variety has likewise a green stalk ; but 

 its feelers are not variegated, being throughout of a pale and transparent red 

 colour. The animal flowers of Mr. Hughes, and the sea-nettle, with a shagreen 

 skin of Mr. de Reaumur, may perhaps belong to this subdivision. 



The last species of these polypes is the hydra disciflora, tentaculis retractili- 

 bus, extimo disci margine tuberculato.f The colour of its body is always red in 

 the summer, but changes into dusky green, or brown, towards the latter end 

 of autumn. The outside of it is quite smooth, some few animals of this sort 

 excepted, which are marked, like the first species of this class, with small pro- 

 tuberances, to which several extraneous bodies likewise adhere. The feelers are 

 constantly inserted into the disk of the polype, but they are of various colours, viz. 

 red, blue, white, and sometimes even variegated. Between these feelers and 

 the membranaceous cover of the animal, is a row of small hemispherical tu- 



* This is the Actinia gemmacea of Ellis. 

 + This is the Actinia mesembryanthemum of Ellis. 

 VOL XI. 3 Y 



