276 Mr. A. H. Hassall's Catalogue of Irish Zoophytes. 



rell's specimen was much smaller than mine, too much stress 

 must not be laid on this circumstance. It deserves to be no- 

 ticed, however, that this specimen had a gall-bladder like the 

 A. neylecta, small yet quite distinct, which Mr. Yarrell's had 

 not. Hence this organ is certainly sometimes present, and at 

 other times absent, in the same species, unless we imagine, 

 which I conceive veiy improbable, that the one here described 

 was different from his. 



The stomach was of the same form as in the A. arvalis and 

 A. neglecta. The liver consisted of seven distinct lobes, five 

 large and two smaller ones. 



I have already stated that this specimen was taken at Abe- 

 rarder, in Inverness-shire ; and Mr. Thompson informs me, 

 that, supposing it to be the A. riparia of Mr. Yarrell, he be- 

 lieves it to be the most northern British habitat for this spe- 

 cies. 



Swaffham Bulbcck, April 2G, 1841. 



XXXIII. —Supplement to a Catalogue of Irish Zoophytes. By 

 Arthur Hill Hassall, Esq. Read before the Natural 

 History Society of Dublin, November 6th, 1 840. 



[With Five Engravings.] 



Mr. Chairman and Gentleman, 



As to many of my hearers the subject of the present commu- 

 nication, entitled a ' Supplement to a Catalogue of Irish Zoo- 

 phytes,' pubhshed in the November Number of the ' Annals 

 and Magazine of Natural History,' may be altogether new, I 

 propose, before entering upon the consideration of it, to make 

 some observations on Zoophytes generally. This course will, 

 1 hope, serve both to interest my audience, as well as to re- 

 lieve, in some measure, the tediousness of a mere enumeration 

 or technical description of species, which, however valuable to 

 science itself, possesses but little to attract or engage the at- 

 tention. The most careless wanderer on the sea-shore must 

 often have noticed the beauty and delicacy of the conforma- 

 tion of these interesting productions, rivalling in their purity 

 and freshness the element which they inhabit and adorn, and 

 have been struck with wonder and admiration at the evidence 

 of designing care which they so remarkably exhibit even in 

 their general appearance. Nor is the beauty and elegance so 

 observable in their outward form diminished by a closer in- 

 spection. If the power of a microscope be applied to them, 

 and their more intimate structure be disclosed, new beauties 



