306 Miscellaneous. 



Gemmules, or round bodies, are sometimes observed in them. The 

 tentacle or tail appears, when very highly magnified, rather flat than 

 round, and marked with delicate transverse striae down its centre. 

 The Noctiluca appears more nearly allied to the PhysalicB than any 

 other family of the Acalephse, and to the genus Alophota of Brandt. 

 Only one species of this genus is known. — A. Olfersii, described by 

 Brandt as "a white bladder or air-vessel the size of a pea, oblong 

 oval, having two tentacula." (See Lesson's Acalephse, p. 559.) 



4. Thaumantias hemisphcBriea (see Forbes' s naked-eyed Medusae, 

 p. 49). Of this beautiful little animal we captured many specimens 

 in the harbour of Lowestoft. They agreed precisely with the descrip- 

 tion given by Professor Forbes, except that we found many specimens 

 with fewer than twenty ocelli and tentacles ; and in all the specimens 

 we examined, there were two or three minute lobes on the margin of 

 the umbrella, between each tentacle. 



We also found three or four other smaller species of Thaumantias 

 in the same locality ; some having the umbrella shaped like a Chinese 

 hat ; — we noted these, vrith some doubt however as to our correctness, 

 as T. pileata, T. sarnica, T. punctata, T. inconspicua, and T. Thomp- 

 soni, of Professor Forbes. 



5. Of the larger Medusae, Chrysaora hyoscella occurred in great 

 variety during two days of very calm, warm weather. From their 

 beautiful markings, viz. light brown bistre colour, with diverging 

 and branching radii, proceeding from a circular line round the centre, 

 and large dark spots round the circumference, they appeared like the 

 tops of so many smaU balloons, floating in the ocean, and attracted 

 general observation. They varied greatly in size, colour, and markings. 

 Rhizostoma undulata 1, Medusa aurita 1, and others of this family, 

 were seen at the same time, but the study of this race of animals is 

 from their nature, and especially from our having no good work re- 

 specting them, beset with difficulties. 



6. We also captured what appeared at first to be a very minute 

 star-fish, but which on examination proved to be one of the young 

 states of a Medusa, as described by Sars. It was about 2 lines in 

 diameter, and swam freely in the salt water. 



7. With the smaller Medusae we also took two specimens of the 

 young state of a Crab, the Zoe pelagica of the older naturalists. 

 These little animals are very active swimmers, and from their trans- 

 parency, their large eyes, and arborescent vessels, running especially 

 about the head, they are very beautiful objects in the microscope. 



8. On the stem of an Alga, growing by the side of the Lock at 

 Lowestoft, we found Bowcrbankia densa, the only specimen we have 

 found on our coast. 



ON THE GENUS HYALONEMA. BY J. E. GRAY, ESQ. 



M. Milne-Edwards, in his work on British Fossil Corals, observes, 

 "The genus Hyalonema established by Mr. Gray (Proceed, of the 

 Zool. Soc. 1835, 63) is also referred by some zoologists to the tribe 

 of Gorgoninte, but the recent observations of M. Valenciennes tend to 

 establish, that the fasciculus of siliceous threads which constitute the 



