DUBLIN NATURAL HISTOET SOCIETY. 69 



Mr. Cocks, however, says: — "That in the neighbourhood of Fal- 

 mouth it is never found on this crab, nor on Pinna ingens ; but fre- 

 quently on Pecten maximus, as well as on Buccinum undatum, and on 

 stones." 



"I do not remember myself ever to have seen it on a bivalve." — 

 Gosse. 



The fact, then, of its being parasitical on Cardium edule seems to be 

 hitherto unnoticed, and is highly interesting with regard to the habits 

 of the species, which must thus spend a considerable part of its time 

 buried in the sand, which adheres to the shell of the cardium. 



I may remark here that the cockles were particularly large, and 

 many of them had within the sheU a minute specimen of the Pea -crab, 

 Pinnotheres prisum. 



In noticing ^S*. parasitica in his list, Dr. "Wright remarks : — " This 

 species would appear to be quite absent from the eastern shores of Ire- 

 land, and I only know of its being taken once in Ireland, in Bantry 

 Bay." 



I^oTE. — Of about 50 cocldes, more than one-half (25) bore anemones. 

 I^one of the cockles bore more than one anemone. 



FRIDAY, APRIL 5, 1861. 

 William Andrews, M. E. I. A., President, in the Chair. 

 The previous Miautes were read and signed. 

 Mk. "William Archee read the following paper : — 



DESCEIPTION OE A NEW SPECIES OF MICEASTEEIAS (aG. ET ALIOEUM, NON 



ehe.), with eemaeks on the distinctions between miceasteeias 

 eotata (ealfs) and m. denticulata (bee'b.). 



To those who in this day advocate the non-existence of Species, it must 

 doubtless seem but a profitless task and an illusory effort to try, by a 

 definition or diagnosis, to fix a boundary to that which they assert is only 

 imaginary ; but they who defend this bold and sweeping theory, how- 

 ever justly celebrated some of their names may be, are, I imagine, still 

 in the minority, though that circumstance, I admit, is in itself far from 

 proving that they have not truth on their side. But, so far as I can at 

 present see, their case, however plausibly put, seems far indeed from 

 proven ; but, on the contrary, geological data, and our experience of 

 the world around us, seem hitherto, at least to my humble judgment, to 

 combine in subverting and disproving it. Species, in the old-fashioned 

 sense of the word — some more, soine less variable — I, for the present at 

 least, conceive to exist, and not less amongst the microscopic forms than 

 amongst those of larger growth. 



It is true that, unless an organism can be traced through its whole 

 course of life — that is, that its development from the resultant germ of 



