Zoology. ) 297 
the Acalephs? and 2d, do all the so-called Acalephs really agree in the 
way in which the plan of radiation is through them exemplified? The 
it with a polyp; for instance an Actinia ;—and first it is plain that the 
jelly-fish carries the so-called stomach of the pop ti turned inside out, and 
formin ng t the proboscis (compare Rhizostoma, Cyanea, c.) 5 even where 
there is no proper proboscis, the stomach is oe Comes into the body 
(Bolina, dic). What is commonly spoken of as the stomach of a medusa 
is nothing more than the visceral cavity, into which open the radiating 
tubes, just as the free chambers of the polyp open into its visceral cavity. 
The jelly-fish has however a circular tube, gine round the edge of 
disc, and m making a common receptacle for all the radiating tubes ; 
feature not found in the polyps. Then the fleshy interambulacral iad 
tions, so thin and regular a polyps, are thickened, among medusa, 
- and coalesce above a below, leaving only narrow, radiating t bes 
through their gellatinous mass ith the model thus hastily sketched, 
; all acne will be found to agree. The tm ich a and 
elella I 
needed he “tentacles ” (hydree) of Velella acoally produce pan medus@. 
Such elongated communities as D ‘iphyes may, in like way, be homolo- 
It cael 
probable. t that the whole of me Edwards’ SHvietaa ham which in- 
cludes sete Pocillop , &e., is to be con nsidered as ‘ag the 
atio in e greatest importance in satan 
a CA prope sitter of Part II, on Ctenophore, could not cs Untcns within 
De limits of this short notice. It consists of a critical analysis of Cteno- 
al; a consideration of their natural families ; me 
ae 
