160 Notes and Memoranda. 



New Parasitic Crustacean. — Annals of Natural History contains a trans- 

 lation of a paper by M. Hesse on a parasitic crustacean living in a small tumour 

 often noticed in young green wrasses,* not far from the eye and the bronchial 

 aperture. This tumour is formed by the entrance of a young crustacean of the 

 order Lernseida under the fish scales, which it displaces as it grows, and eats a 

 hole in the flesh. The body is fusiform ; head small, rounded at the apex, bearing 

 above a median eye, a proboscidiform process with denticulated jaws, and three 

 pairs of prehensile footjaws. 



Dialytic Action oe India Ettbbee and Metals on Gases. — A paper by 

 Mr. Graham will be found in Proceedings of the Royal Society, 86, on this sub- 

 ject, in which it is stated that a thin film of caoutchouc has no porosity, and is really 

 impervious to air or gas ; but the same film is capable of liquefying the individual 

 gases of which air is composed, while oxygen and nitrogen, in the liquid form are 

 capable of penetrating the substance of the membrane (as ether and naphtha, etc.), 

 and may again evaporate into a vacuum, and appear as gases. When thus 

 acting on air, oxygen is absorbed two and a-half times more abundantly than 

 nitrogen. The penetration by hydrogen of platinum and iron tubes, discovered 

 by M. M. St. Claire Deville and Troost, is supposed by Mr. Graham to be con- 

 nected with " a power resident in these and other metals to absorb and liquefy 

 hydrogen, possibly in its character as a metallic vapour." Palladium foil at 100° C. 

 coudenses 613 times its volume of hydrogen, but has no absorbent power for oxygen 

 or nitrogen. Mr. Graham observes, " It is believed that metallic pores, and indeed 

 all fine pores, are more accessible to liquids than to gases, and in particular to 

 liquid hydrogen." 



Cong-elation and Death oe Animals. — Dr. Davy, finding that a statement 

 made by him many years ago, to the effect that a leech might be frozen without 

 loss of life, was contradicted by more recent experiments of M. Puget, has repeated 

 his investigations on leeches, frogs, etc., and he arrives at the conclusion that "the 

 thorough congelation of an animal is incompatible with life." It is still, however, 

 not certain to what extent congelation may be carried without death necessarily 

 ensuing. What, for example, are we to make of the story of the frozen carp told 

 by Sir J. Franklin, and cited by Mr. Couch. The amount of freezing in these 

 cases may have been nearly complete. Dr. Davy's paper is in Proceedings of the 

 Royal Society, 86. 



Magnetic Action oe the Moon. — Proceedings of the Poyal Society, 86, 

 contains a paper by Lieut.- General Sabine, F.R.S., on the lunar diurnal variation 

 of the magnetic declination, and of the horizontal vertical components of the 

 magnetic force, derived from seven years Kew observations, and from comparison 

 with observations in other parts of the world. The paper states that " a magnetic 

 variation shown to be thus obviously dependent upon the moon's position rela- 

 tively to the terrestrial meridian, and agreeing in its principal features in such 

 various localities, is urged by the author as being ascribable, with great proba- 

 bility, to the direct magnetic action of the moon." 



Crystallizing Carbon. — M. Lionnet gives the following process in Comptes 

 Pendus : — Take along thin leaf of gold, or better of platina, and wind round it 

 a helix formed of a similar tin leaf, so that the covered and uncovered portions 

 of the platina shall be about equal. With the metallic couple thus formed a 

 spiral is made, and plunged into sulphide of carbon. The sulphide is slowly 

 decomposed, the sulphur combining with the tin, and the carbon being precipi- 

 tated in crystals. 



* For an account of the wrasses, see Couch's Fishes of the British Islands. 



