300 CONTRIBUTIONS TO THE NATURAL HISTORY 



tubes, and two of the same length intervening between two tubes, and alternating 

 with shorter ones ; the mouth forming, as in the other species, a small bell-shaped 

 peduncle, with four lobes spreading sideways and fringed along their margins ; the ova- 

 ries attached in the shape of ovate bodies on the lower side of the xhymiferous tubes, 

 about the middle of their length. This species is very minute, scarcely 

 a line in diameter, and perfectly transparent and white, excepting the 

 dark eye-specks at the base of the tentacles, the ovaries having a light 

 tint of yellow. 



I propose to call this species Thaiimantias diaphana. I subjoin a 

 wood-cut of the rough sketch made at the time. It was dredged with 

 a gauze net from the surface, on the 25th and 26th of June, 1849. 

 Fig. 1 represents this little Medusa as seen from above ; Fig. 2 shows 

 it in profile. 

 While this sheet was passing through the press, Mr. Charles Girard, my assistant, 

 brought me another species of Thaumantias, taken by him on the beach at East 

 Boston. Though it was in a rather indifferent state of preservation, I could satisfy my- 

 self that it differs specifically from the former, inasmuch as it has narrow, elongated 

 ovaries ; thus showing that the two types of Thaumantias which have been noticed in 

 Great Britain occur also along the shores of the United States. The size and time 

 of appearance speak also in favor of the specific difference of these two Medusae, as the 

 first, observed towards the end of June, was very small, and the other, caught early in 

 May, was a full grown-animal, over one inch and a half in diameter, and similar in 

 form to Thaumantias Pilosella. 



STAUROPHORA. 



The genus Staurophora was established in 1835, by Professor Brandt, in his Prodro- 

 mus of a Description of the Animals collected during a Voyage round the World by 

 H. Mertens, published in the Transactions of the Imperial Academy of Sciences of 

 St. Petersburg, in 1835. 



The genus was established by Brandt from the drawings and memoranda of Mertens. 

 Afterwards, a fuller account of it was given by Brandt, in his extended Description of the 

 Medusae collected by Mertens, published also in the Transactions of the Imperial Academy 

 of St. Petersburg, in 1838, Sixth Series, Part Second, Vol. II. p. 399. 



The genus is characterized as follows : — No mouth, according to Mertens ; — on 



