Spermatophorce of molluscous Cephalopoda, 8fc. 73 



years ago in the Crustacese, and which M. Brant has since 

 found in a great number of invertebral animals. 



Observation on the sex of Echini. The separation of sex 

 in the gasteropodous Mollusca is not astonishing, but what 

 will surprise you I presume is, that in the Echini there exists 

 male and female perfectly distinct. This curious fact has 

 latterly been stated by M. Peters, and I have since often 

 had occasion to verify the assertion ; externally the testicles 

 of Echinodermata differ in no respect from the ovaria, but the 

 liquid which they contain is of a milky whiteness, instead 

 of being orange as in the females ; it furnishes zoosperm, 

 the tail of which it is difficult to perceive, and the move- 

 ments of which are characteristic. 



Structure and sexual organs of Dendrophylli. I have 

 sent you also a drawing which demonstrates the external 

 conformation and the internal structure of calcareous polypi- 

 ferous polypi, of which M. de Blainville has formed the 

 genus Dendrophyllus. If we judge of these animals by the 

 figure which has been given by Donati, and which the 

 greater part of modern authors have reproduced, we shall 

 believe them possessed of the most confused organization ; 

 but the tentacles in the form of pincers which we supposed 

 surrounded their mouth does not exist, and their structure 

 both internal and external differs little from that of the 

 Actiniae, and principally from the Caryophilli, properly so 

 called, analogy proves it so ; but I have moreover demonstrat- 

 ed that these coralligenous polypi, the same as the superior 

 animals, possess distinct sexual organs ; some have ovaria, 

 while others contain in the place occupied commonly by 

 the female organs, testicles of the same form as the ovaria, 

 and containing instead of eggs, spermatic animalculae. You 

 may see one of these zoosperm figured in the above men- 

 tioned drawing. 



Observations on the structure of Acalephce Hydrostaticce. 

 I have also had occasion to study some of these singular 



L 



