Miscellaneous. 285 



ing, hoping to gain more complete knowledge of a difficult and much- 

 confused branch of zoology. Having now however examined more 

 than twice the recorded number of British Medusae, and become ac- 

 quainted with numerous new specific and several new generic forms 

 of great interest to the naturalist, he ventures to lay before the Sec- 

 tion an outline of the data in his possession. These data are in great 

 part due to the opportunities afforded him by his voyages round the 

 coasts of Britain with his friend Mr. M'Andrew. After pointing 

 out the difficulties attending the study of these animals, and giving 

 a brief view of the present state of the subject generally, Prof. Forbes 

 insisted on the necessity in future of naturalists abstaining from pub- 

 lishing imperfect observations respecting them, and urged the adop- 

 tion of the descriptions of Milne Edwards, Sars and Will as models 

 for those who were ready seriously to engage in the study. He 

 called attention to the important observations on their development 

 lately made by his friend Prof. Reid of St. Andrews, and expressed 

 a hope that ere long the return of the Arctic expedition would 

 bring a great mass of new materials of the most accurate description 

 through the observations of Mr. H. Goodsir. In grouping the British 

 species, Prof. Forbes calls attention to the mutual correspondence of 

 certain characters ; viz. of the condition of the reproductive, digestive 

 and sensitive systems. He proposes to group all the British Medusae 

 under such as have hooded and such as have naked ocelli. The first 

 character is combined with a conspicuous and comparatively com- 

 plicated reproductive system, and a ramified gastro-vascular appa- 

 ratus. All the Pulmograda with naked ocelli have simple vessels, 

 with one exception, — a new and most beautiful generic form, the 

 type of a subsection by itself. The remainder form three natural 

 groups, as will be seen in the following general table, exhibiting the 

 arrangement of the British Pulmograde Medusa? : — 



1st Section.— Hooded-eyed ; ramified gastro-vascular system. 

 1st Genus. — Rhizostoma (Cuvier). 1 species, R. Aldrovandi. 

 2nd Genus. — Cassiopea (Peron). 1 sp. C. lunulata. 

 3rd Genus. — Pelagia (Peron). 1 sp. P. cyanella, one of the most 

 phosphorescent and beautiful of European Medusae, now first 

 announced as British, having been taken during the past month 

 by Mr. M'Andrew and Prof. Forbes off the coast of Cornwall. 

 4th Genus. — Chrysaora (Peron). 1 sp. C. hysoscella. 

 5th Genus. — Cyanea (Peron). 2 sp. C. capillata and C. Lamarckii, 



both common ; very large, stinging Medusae. 

 Cth Genus. — Medusa (Linnaeus, Escholtz ; Aurelia, Peron). 2 sp. 

 M . aurita and M. cruciala (the latter is the Medusa so abundant 

 in Southampton Harbour). It has white ocelli. 

 Many more spurious species of Cyanea, Medusa and other genera 

 are recorded by Peron, Lesson and others, and enumerated as inha- 

 bitants of the British Channel. After careful consideration, they 

 have been rejected as mere varieties from this arrangement. Certain 

 forms belonging to this section recorded by Pennant and Templeton 

 are also rejected as too imperfectly observed to be of any service to 

 science. 



