ZOOLOGY AXD BOTANY, inCEOSCOPY, ETC. 747 



In giving an account of lAzzia grata, the author points out that 

 Lizzm passes through a Dysmophorsa and Margellium stage, and has 

 the power of germination throughout them both, and he concludes 

 that Haeckel is not justified in his formation of new genera " on what 

 are surely embryonic features." 



3Iahella (M. gracilis) is a new genus in which alone budding 

 takes place from the proboscis of a hydroid medusa with eigfd, or 

 more than four, chymiferous tubes. 



Modeeria midtitentacv.la is a new species described from the 

 notes and sketch made by A. Agassiz. Dinematella (D. cavosa) is 

 another new genus, the examples of which have often been confounded 

 with Stomatoca apicata ; it differs, however, in the colour, shape of the 

 ovaries, and by the presence of a cavity in the apical portion of the 

 bell ; the contents of the cavity are liquid, and identical with that 

 found in the marginal and radial tubes ; but the space does not seem 

 to be, as in Ctenaria, a brood-pouch. 



After notes on several forms already described, we come to 

 Eutiraa gracilis n. sp., which is distinguished from its allies by the 

 presence of a pair of lateral " spurs " or thread-like appendages on 

 each of the rudimentary tentacles. A new genus of the Tracliyneraidos 

 is Sphcerula (S.formosa) which is allied to Euryhiopsis ; there is no 

 peduncle to the proboscis, and there is an open cruciform mouth ; 

 no oral tentacles or knobs. Cunina discoides is a new species. 



Towards the conclusion of his paper the author enters into a 

 descriptive and critical account of the sense-organs found on the bell- 

 margin of Cyanea arctica, and describes certain structures which he 

 thinks previous naturalists have overlooked. 



^quorea Forskalea.* — Prof. C. Glaus, while giving an accoimt of 



this Adriatic Medusa, takes the opportunity of making some criticisms 

 on Prof. Haeckel's classification of the ^quoridoe. A careful study of 

 this form has shown Glaus that it is subject to extreme variation ; 

 variations so great as to have led Prof. Haeckel to make a number of 

 genera and sub-genera for their reception. It is not possible to 

 abstract a critical paper of this kind, and we must be content to 

 direct attention to the following points. Glaus finds that the colour 

 varies with age and sex ; the young may well be called vitrina, as 

 Gosse called them ; later on blue pigment-granules may appear in 

 the ectoderm, and especially in the gonads of the male, while the 

 female may take on a more or less reddish coloration (the A. violacea 

 of Milne-Edwards). The radial canals vary in number from just over 

 fifty to nearly eighty. The form and size of the mouth-lips depend 

 on the state of contraction of the specimen, on its age, and on the 

 breadth of its umbrella. Altogether, according to Prof. Glaus, 

 Haeckel would seem to have afforded a very interesting proof of the 

 origin of species by variation. 



Notes on Linmocodium.t — Professor Bay Lankester has been able 

 to make a study of the endodermal cells of the fresh-water Medusa 



* Glaus' Arbeiten, iii. (1881) pp. 283-312. 



t Quart. Jour. Micr. Sci., xxi. (1881) pp. 119-31 (3 pis.). 



