156 Scientific Inielligence. 
cation does exist between the organs and the surroundin me- 
dium, it is by means of simple orifices in the walls of the cavity.” 
os "6 Siete ecw ges apparatus” of “Vermes” is so diverse in 
tru and position in the different groups, as 46 render it 
ora seraternas whether these organs are homologous in the dif- 
ferent orders. Moreover; there is still so much to learn concern- 
connections, lacune, hese: ete. It should ae be considered 
that no “ segmental organs” have yet been detected in the nearest 
iopods is nen oe one of their most sacaitcatie characters; and 
mate one of the strongest analogies with the Annelids which they 
poss 
The character of the nervous system of Brachiopods, according 
to the author’s own statements, is quite as much mere that _ a 
median line beneath, crete like many leeches, lay eggs enclosed in 
— not unlike those of many mo usks. Other exceptions 
also occur in the pomeees while among the Cestodes, Trematodes, 
Hans atodes, and Turbellaria, the oviduct is usually single mers 
Polyps directly with the ovary, as in most Mollusca. But 1 
oy 
hardly ara 
lids. In the Molineux. “with the exception of the Octopoda, the 
oviduct is single.” Many other — oceur, in the Chitons, 
Lamellibranchs, ete. “ Among the Mollusks, even when devoid of 
a shell in the adult, the embryo oe dueélons a shell composed of 
one or two pieces.” This is not the case in many Cephalopods 
and Pteropods. 
