268 BOPYRIDA. 
by Mr. Henry Goodsir in the ‘f Edinburgh New Philoso- 
phical Journal for 1843,” where he erroneously described 
the female, or the animal represented in our right-hand 
figure, as the male of the cirriped (Balanus balanoides), 
and the animal, copied in our left-hand figure, as being 
parasitic upon that supposed male. 
About the time of the publication of a memoir in the 
* Annals of Natural History,” ‘‘ On the Development of 
the Cirripeds,” in 1851, our attention was drawn to a fleshy 
mass of material that we found attached to the base of 
the animal of the Bal/anus balanoides, lying within the 
shell. ‘This we first took to be the ovisac of the Balanus, 
because we found it always full of ova, which we then 
thought were the ova of the Balanus in one particular 
stage. In this we thought we were confirmed by the 
fact that we never found the ova of Balanus in the condi- 
tion most familiar to us in any of those specimens where 
these ova were found. A drawing of the mass, which 



DEVELOPMENT OF LARVA OF CRYPTOTHIRIA BALANI., 
we submitted to Mr. Darwin, induced him to suggest it 
as being the parasite that Mr. Goodsir described as the 
male of the cirriped; and an examination of the article 
“On the Sexes of the Cirripeds,” clearly showed us that 
