74 CLASS Il. 
Rozs. Zns. 11. Polyp. Tab. 84, 85, 87; Trempiey performed most 
of his experiments on these last two species. Comp. what is said 
at pp. 67, 69. 
On this genus compare the work of TREMBLEY, noted in p. 60, and of 
LavrEnt, p. 68. The first discoverer of the genus was LEEUWENHOECK, who 
probably observed Hydra grisea. He announced this animal in a letter to 
the Royal Society of London, of Dec. 25, 1702, observed its propagation 
by gemmation, figuring it with two young ones, and especially described 
the great contractility of the arms. Phil. Trans, No. 283. Vol. Xx11. for 
the years 1702, 1703, pp. 1304—1311. This description, however, had 
been forgotten when TREMBLEY discovered the animal a second time. 
Clava Guet. Ooryne of authors, not of GAERTN. Body cla- 
vate. Tentacles scattered. 
These animals are marine, and adhere to different bodies. Propa- 
gation is effected by buds of a round or bell-shaped form, which 
contain ova or spermatozoa, and which occasionally detach them- 
selves from the stem on which they were developed, swim freely 
about, and resemble small Meduse. 
Sp. Clava parasitica Gu., Hydra multicornis, Forskau, Icon. Rerum natur. 
Haunice, 1776. Tab. xxv. fig. b, B. Cor. squamata MUELL. Zool, Danic. Tab. 
Iv. about three lines, according to RATHKE, 3inch long. RATHKE dis- 
covered Spermatozoa in the swellings called Squame by MUELLER ; vid. 
WIEGMANN’S and Ericuson’s Archiv. f. Naturgesch. 1844. 8. 155-——165 ; 
Ann. des Sc. Nat. 3ieme Série. 11. 1844. Zool. pp. 201—210; WAGNER found 
eggs in these swellings, con. Zootom. Tab. xxxIv. fig. 16. Thus the sexes 
appear to be distinct. 
Eleutheria QUATREFAGES. Body hemispherical, hollow. Ten- 
tacles six, divided into two retractile branches, terminating in a 
round head. Six eyes placed at the base of the tentacles. 
Sp. Eleutheria dichotoma, Dx QuATREFAGES, Mémoire sur l Eleutherie dicho- 
tome. Ann. des Sc. nat. sec. Série. Tom, XVII. 1842. Zool. pp. 272—288, 
Pl. vu. Discovered in the Atlantic ocean, on the shore of the Islands 
Chausey, Dep. La Manche, 3 millim. in diameter. There were eggs in the 
posterior part of the body. This form is probably a free bud for the propa- 
gation of some species of Coryne, Sertularia or Tubularia. See V. BENEDEN, 
Bulletin de? Acad. Royale de Bruxelles, Tom. X1. No. 10. QUATREFAGES, 2b. 
Tom. x11. No. 2. 
[Genus Pedicellaria MvELt. delendum!. | 
1 Pediculated organs with three valves are found between the spines and tentacles, 
or suckers, of the sea-urchin, which MUELLER took to be parasitic Polyps, and of which 
he formed the genus Pedicellaria. 
a eB 
