Dr. B. Seemann on Hanburia. 9 
the body dilated from the periphery and bent round into the 
form of an umbrella or bell, without implicating the stomachal 
cavity in the change. The stomachal cavity then remains, some- 
what as in the Oceanide, limited to the centre of the umbrella 
thus produced. The arms, with the ocelli and the annular vessel, 
on the contrary, advance by the whole length of the radii of the 
umbrella from their previous position, with which, of course, is 
’ associated a corresponding elongation of the radial canals. 
In conclusion, as regards the relationship of Eleutheria to 
the established Medusoid genera, it has recently been placed by 
Gegenbaur, and as it appears to me with perfect justice, in the 
- vieinity of the genus Cladonema, Duj. ( Zeitschr. fiir wiss. Zool. 
Bd. vii. p. 280). In fact, both in structure and mode of life 
there appear to be many remarkable agreements between the 
two. In connexion with the first point, we must cite first of all the 
dichotomous division of the arms, which is certainly carried 
further in Cladonema during the development on the parent 
polype-stock (Stauridium), but still agrees perfectly with that 
occurring in Eleutheria*, and secondly the comparatively high 
organization of the ocelli. As regards the second point, we 
know already from the observations of Dujardin that Cladonema 
sometimes, like Hleutheria, fixes itself by its arms, and remains 
for a considerable time in this state of repose. In the harbour 
of Messina, where this Medusa not unfrequently occurs, it lives 
chiefly, according to my observations, upon a confervoid Alga, 
which covers the sea-bottom in abundance, and it appears to 
come but rarely to the surface of the sea. 
I1.—On Hanburia, a Cucurbitaceous Genus from Mexico. 
By Bertuorp Seemann, Ph.D., F.L.S. 
In August 1854, Mr. William Schaffner found near Cordova, in 
the “ Sierra caliente” of Mexico, a Cucurbitaceous plant with a 
fruit resembling in outward appearance the well-known ‘ Cha- 
yote” or “Chayotl” of the Mexicans (Sechium edule, Jacq.), 
and bearing, on account of that resemblance, the vernacular 
name of “ Chayotilla.” A few seeds of it, which he transmitted, 
were, together with a collection of dried plants, purchased b 
the Royal Botanic Gardens at Kew; they were planted, but did 
not germinate. These seeds were flat, nearly orbicular in cir- 
cumference, and about 2 inches long, having a very thin mem- 
* Dujardin, J. c. 1843, tome xx. p. 372. According to Keferstein and 
Ehlers (‘ Zoo}. Beitr.’ 1861, p. 86), no more indication of a further ramifica- 
tion is to be detected in the arms of free young Cladonemata, measuring 
08 mill. across the umbrella, than in Eleutheria. 
