264 Dr. A. Grisebacii on Phytosoa in Phanerogamous Plants. 



These conclusions are founded upon imperfect and erroneous 

 data that might have been avoided by consulting the papers on 

 Scottish Nudibranchiata in the first volume of this Journal. Dr. 

 Jol nston there institutes the genus Triopa for the Doris clavi- 

 geia of INIiiller, but while taking this species for his type he ac- 

 knowledges that he has characterized the genus rather loosely on 

 prrpose to include in it another animal not very perfectly under- 

 stood, which I have since suggested may be the young of a Po- 

 lycera. Now from this circumstance it does not necessarily fol- 

 low that Tj-iopa clavigera is also a Pohjcera. In calling the latter 

 species an Euplocamus, Professor Forbes followed the opinion of 

 JDr. Philippi himself, who in describing the genus (Enum. INIoll. 

 Sicili?e, vol. i. p. 104) says, " Altera hujus generis species est Doris 

 clavigera, 0. Fr. Miiller, Zool. Danica," thus referring to his ge- 

 nus a species without lateral branchife ; and he has since united 

 this genus with Idalia, Leuck., in which lateral branchiae are also 

 wanting. 



If, as Dr. Philippi states, and I am inclined to believe, the ty- 

 pical Euplocami have lateral branchiae, it is an interesting cir- 

 cumstance, as it will be the only genus in which the two kinds of 

 branchiae are known to exist in the same animal. 



On this view of the subject, I should propose that the genus 

 Euplocamus be retained for E. croceus and E. 7-ajnosus, and that 

 Do7'is clavigera, Miill., be considered the type of the genus Triopa, 

 to which may perhaps be added Doris fimbriata and D. lacera of 

 the same author. 



Idalia cerrhigera and /. laciniosa are very properly placed in 

 the genus of Leuckart. 



XXXVIII. — On the Occurrence of Phytozoa in Phanerogamous 

 Plants. By Dr. A. Grisebach*. 



The observation recently published by Nageli, that the tailed 

 globules which occur in the antheridia of mosses are likewise 

 found in organs possessing a similar structure on the germ-leaf 

 of ferns, excited my interest, the more so as in this case it is requi- 

 site to abstract these globules entirely from any connexion with the 

 production of spores or with any process analogous to impregna- 

 tion in animals. I examined these organs fii'st on a germinating 

 Adiantum concinnum, Kth., and had occasion to confirm Nageli^s 

 discoveiy in every essential point. I will here mention the re- 

 markable phaenomenon, that in Adiantum these organs, which, to 

 prevent any comparison with the anthers, I have called Corynidia, 



• From the Botanische Zeitung, Sept. 20, 1844. Translated by W^ 

 Francis, F.L.S. 



