July 6, 1893J 



NA TURE 



of salts in water, alcohol, pyridine, amyl alcohol, and acetone, 

 Herr Schiiarock (Zeitschrift fiir phydkalische Chanie, xi. 6, 753) 

 concludes that the specific rotation of a salt is independent of 

 the concentration, and of the nature of the solvent, and that there 

 is therefore no evidence of effects which might be attributed to 

 electrolytic dissociation. Dr. Perkin pointed out in 1889 that 

 the molecular rotation of chlorhydric acid calculated from the 

 behaviour of a solution in water was twice as great as the value 

 deduced from a solution in amyl oxide. This result has been 

 employed by the upholders of the " new " theory of solutions as 

 clearly indicating the eflfect of electrolytic dissociation. Herr 

 Schiinrock finds, however, that chlorhydric acid reacts chemically 

 with amyl oxide, and that if allowance be made for this reaction, 

 chlorhydric acid exerts the same effect on polarised light when 

 dissolved in amyl oxide as when dissolved in water. In the 

 same communication values are given for the specific and mole- 

 cular rotations of some fatty and aromatic hydrocarbons, fatty 

 alcohols, &c., and relations are established between the magni- 

 tudes of these constants which are similar to those discovered by 

 Dr. Perkin. The rotations of solutions of double salts are also 

 treated in the paper. 



At a recent meeting of the Berlin Society of Naturalists, Herr 

 Ascherson spoke on the metallic-looking deposit often found on 

 the teeth of ruminating animals in Southern Europe and the 

 East. Hertwig described a silver-like crust on the back 

 teeth of a goat in Xante, as composed of fine lamellae, 

 and of calcium-carbonate with some iron. In most cases, 

 however, the coating is rather of a gold, bronze, or brass 

 colour, and the yellow pigment is probably of organic origin. 

 It is more common to meet with the deposit on the molars of wild 

 raminants (especially antelopes) than on those of domesticated 

 animaU. Natives of the Mediterranean region say the gold 

 colour is due to eating a mysterious, light-giving plant, very 

 difficult to find, but much desire.l, as it changes all that it 

 touches to gold, or indicates gold in the ground, or can be used 

 for gold-making. Various plants have been specified as the 

 source of the deposit, one being the Lebanon poppy, the ground 

 leaves of which have a remarkable golden look, very similar to 

 that of goats' teeth, so that a causal relation between ths two 

 has seemed natural. Dried remains of the plant, too, have a 

 bright metallic lustre. An examination by Herr Graebner shows 

 the gold colour to have its seat in the moderately thickened 

 cell membranes of the tissues concerned ; but the shining look 

 apparently comes from a thick deposit of wax on the epidermis. 

 The teeth of certain fossil ruminants have been found with 

 similar incrustations, e.g. molars of Samotherium from the 

 miocenc of Mitylene in Samos. 



At the bottom of the valley of St. Martin, near Millau (Avey- 

 ron), the Boundoulaou grotto pierces the calcareous rocks of a 

 promonto y of the Larzac. There are four entrances on the 

 face of the cliff; the most practicable lies on the western flank 

 at a height of 535 m., and may be reached with the help of a 

 ladder 14 m. long. It was explored last autumn by M. E. A. 

 Martel, who, in conjunction with M. Emile Riviere, describes 

 hit finds in the Comples Rmdus. It was found to consist of three 

 galleries, one above the other, the lowest of which contained a 

 lake which fed two perennial springs emerging at a point lower 

 down. This lake was explored with great diflficulty in a canvas 

 boat under a vault hardly i m. high. In the middle of the cave 

 was found a kind of dome 25 m. high and wide, evidently hol- 

 lowed out by water. In the upper gallery, 15 m. above the 

 level of the lake, the explorers encountered a neolithic bone 

 deposit containing a large fragment of pottery, a well-made 

 cylinder of bone, and seven human skeletons. Three of these 

 were arranged side by side under a sort of shed of rocks, with 

 their heads touching each other. It seemed as if these persons 

 NO. 1236, VOL. 48] 



had been surprised and drOwned by a sudden flood of the lake 

 below. One of the skulls is that of a young male adult re- 

 markable for the thickness of the cranial bones and for the want 

 of complexity in the sutures. The second complete skull belongs 

 to a subject not completely grown up, and probably of ' he 

 female sex. Besides these skulls many other human remains 

 were found, including six mandibles, seven humeri and one 

 cubitus, three femurs and five tibias, and one left ilium, 

 amounting in all to traces of seven skeletons. Speaking 

 generally, the type resembles that of the Cavernede I'Homme 

 Mort (Aveyron). An interesting relic also found was a bone 

 cylinder made of the diaphysis of a human femur, and probably 

 representing an amulet or a trophy of war. 



A BIOLOGICAL station has been recently started on Heligo- 

 land. According to the recent report of the director, Herr 

 Heinke, it contains, with other rooms, six workrooms with 

 excellent light, one for the director, two for the assistants, a 

 fourth for Dr. Kuckuck (who is engaged on the marine fljra of 

 the island), while the two others are for "ambulant "naturalists. 

 The conditions of occupation of these will soon be published. 

 The cellar space is being arranged for aquaria. Several boats 

 with dredging and fishing apparatus are at the disposal of the 

 inmates. One of the.se is a launch with petroleum motor ; it 

 has a small cabin, with cooking-stove, &c., so that the whole 

 day can be spent comfortably on the sea. In the summer 

 months arrangements will be made for excursions of several 

 days. A few months' researches on the fauna and flora round 

 Heligoland have revealed a greater richness in these than had 

 been supposed. New forms, not before observed in the German 

 North Sea, have come to light almost daily. The ichthyologist 

 finds Heligoland a rich field ; and interesting studies can be 

 prosecuted on the larval forms of Crustacea, on mimicry and 

 protective colours in marine animals, and their relations to 

 marine plants, &c. 



Mr. Thomas E. Bean contributes to the Enlomohgist for 

 July the results of a fairly extensive breeding of Colias Chris- 

 tina and C. elis, undertaken with a view of determining 

 whether more male or female butterflies are produced. From 

 seventeen separate broods of C. Christina, u6 males and 143 

 females were raised, and nine broods of C. elis gave 32 

 males and 69 females. All the families were subjected 

 to uniform treatment and condition, hence the results show that 

 some cause or causes control the development of sex entirely 

 apart from the influence of variations in nutrition. The sex 

 proportions do not seem to be determined by the seasonal stage 

 at which the eggs are laid, and Mr. Bean thinks that in some 

 cases at least sex is dependent upon antecedent causes, the in- 

 fluence of external conditions not applying. 



A NlJMRER of special articles contributed to the Hampshire 

 Observer, by the Rev. R. H. Clutterbuck, on the Whites of 

 Selborne, Fyfield, and Abbots Ann, will shortly be published 

 at the office of the journal, Winchester. 



Messrs. Dulau and Co. have just issued parts xxiii. to 

 xxvii. of their catalogue of zoological and paliEontological 

 works. They include works on general Entomology, Coleop- 

 tera, Diptera, Hemiptera, and Hymenoptera. 



Mr. James Britten and Prof. G, S. Boulger have reprinted 

 from the Journal of Botany their " Biographical Index of 

 British and Irish Botanists." It is largely rewritten, and com- 

 pleted down to the end of 1892, giving the names and other in- 

 formation respecting all British (and Irish sic] botanists known 

 to the editors who had died before that time. It contains 1825 

 names. 



The Ealing Microscopical and Natural History Society has 

 issued its sixteenth annual report. In it are given abstracts of 



