388 



NATURE 



[August 25, 1881 



Alcohols form an exception, having a comparatively hif;h 

 specific heat ; they gave the differences g'7 and S"5 respeciively. 

 Isomeric substances of similar comiJosition have the same mole- 

 cvilar heat, while those of unlike composition have 'a different. 

 In the tables which give carbon and hydrogen differences there 

 are exceptions along with regularity. For a right development 

 of the theory Herr von Reis feels that more extended observation 

 is necessary. 



The idea of qualitative analysis of substances by microscopical 

 examination of crystalline forms is worked out to some extent by 

 Herr Lehmaun (WieJ. Ami., No. 7). A shallow watcli-glass 

 is Jubstitnted lor the cover glass, and serves for turning over in 

 various ways tlie crystals which form in the inclosed solution. 

 The domain of regular forms is avoided as unsuitable, and only 

 irregular forms observed — the so-called growth-lorms, crystal 

 skeletons, trichites, &c., produced by acceleration of crystallisa- 

 tion, viscosity, and so on. For details of Herr Lehmann's 

 method and apparatus we must refer to his paper. 



Herr Schuller has lately described to the Hungarian 

 Academy of Sciences (Wied. Ann., No. 7) a mercury air-pump 

 which works automatically, and in which all greased glass com- 

 binations are dispensed with, the hermetic closure being effected 

 with only gloss and mercury. The evacuating power of the 

 apparatus was not exactly measured ; there are proofs that it is 

 high. 



Mr. J. Milne has written a careful account of the vertica 

 and horizontal motions accompanying the earthquake of March 

 8, 1881, in Japan. This is believed to be the first earthquake in 

 which a complete continuous record of both components of the 

 motion has been obtained for a period exceeding twenty- five 

 seconds. The actual maximum displacement appeared to be 

 about I '33 millims., recurring at the rate of about seven vibra- 

 tions in five seconds. From the phenomena of this shock, ar.d 

 from some experiments on artificial earthquakes produced by 

 letting an iron ball weighing about one ton fall from a height of 

 about thirty-five feet, Mr. Milne argues that the waves that are 

 felt are transverse to the line of propagation of the shock. 



BIOLOGICAL NOTES 

 Relations betveen the Cr.\nium and the Rest of 

 THE Skeleton. — These relations form the subject of a paper 

 by M. Manouvrier, rer.d at the last meeting of the French Asso- 

 ciation. The following are the author's conclusions: — I. The 

 weight of the cranium varies, in a general way, with the weight 

 of the skeleton, but not proportionally, like the weight of the 

 brain. 2. The weight of the skeleton, less the cranium, in a 

 given race, varies nearly in proportion to the weight of the 

 femur. 3. The weight of the cranium is greater relatively to 

 that of the femur, the lighter the latter is. 4. The weight of 

 the cranium is much more considerable relatively to that of the 

 femur in woman than in man. 5. This sexual difference is so 

 pronounced that it constitutes one of the best secondary sexual 

 characters. About 82 women in 100 have the cranium heavier 

 than the two femurs, while 82 men in 100 have it lighter. 6. 

 The lower jaw is heavier relatively to the cranium in the anthro- 

 poids than in man, is inferior than in civilised races, in man than 

 in woman, and in the adult than in the child. 7. The weight 

 of the cranium is smaller relatively to that of the lower jaw, the 

 heavier the latter is, &c. 



The Colour Changes of Axolotl.— Prof. Semper has 

 lately examined axolotl with regard to the influence of light on 

 its colour (lyU/zburg Phys. med. Ges.). When young axolotl 

 are reared in darkness they become quite dark ; nearly as dark 

 in red light; in yellow, on the other hand, pretty bright; and 

 brightest in bright daylight. The difference is connected not 

 only with the chromatic function found in various degrees in 

 all amphibia, but on pronounced formation of a pecuhar difluse 

 yellowish green colouring matter, increase of white, and diminu- 

 tion of dark chromatophore=. Further, when axolotl are exposed 

 to daylight in white dishes covered with white paper, much less 

 dark pigment forms in them than w lien they are kept in white 

 dishes without a paper cover (other things equal) ; though in the 

 latter case they are apparently exposed to the most intense light ; 

 these darker axolotl are, however, still much brighter than those 

 reared in red light or in darkness. Since (as experiment showed) 

 the white covering paper let through much light, but very little 

 of the chemical rays, it appears that chemical rays play no part 

 la the formation of pigment. I'ut the causes of the whiten'ng 



in bright daylight and the darkening in absence of light remain 

 unknown as before. 



Siredon Lichenoides.— Mr. W. E. Carlin publishes in the 

 June number of \.\\s Proceedings o( the United States National 

 Museum some very interesting details about this remarkable 

 form. Its chief habitat is a body of water some tw o and a half 

 miles in circumference called Como Lake. This has no known 

 outlet, but is fed by a perennial stream of pure spring "water. 

 The lake is shallow, and its water very strongly impreg- 

 nated with an alkali ; it is very disngieeable to the taste. 

 The Shedon never enter the freshwater stream ; they abound 

 in the alkaline waters of the lake in immense numbers. 

 When about one hundred and fifty were placed in fresh water 

 they seemed to suffer no inconvenience, but it had a remarkable 

 effect in hastening their metamorphosis into the Amblystoma 

 form. Of an equal number kept in fresh water and in the lake 

 water, quite a change occurred with the former after twenty-four 

 hours, while the latter showed no change after several days of 

 captivity. Those that were kept well fed in jars usually began 

 to show a slight change in from two to three weeks, and all of 

 them comple:ed the change into the Amblystoma inside of six 

 weeks, while in some kept, but not specially fed, there were but 

 three changes in three months. Specimens kept in captivity 

 became quite tame, soon learning to know that tapping the jar in 

 which they were, meant a fly, and, rising to the surface, wonld 

 snap at whatever they saw first, pencil or fly. 



Fish Mortality in the Gulf of Mexico.— We glean a 

 few more particulars as to this strange mortality from the June 

 Proceedings of the United States National Museum. The fishing 

 interest of Key West is an important one, supplying thousands 

 with the means of subsistence. The fishermen state that a vol- 

 canic spring exists, the waters from which are of a high tempera- 

 ture. The polluted waters are of a red brick colour ; their 

 influence is seen for a distance of 200 mile-. A scant supply of 

 sea water from the Gulf of Mexico sent to Washington was 

 examined by Mr. F. M. Endlich of the Smithsonian Institution. 

 That in which the fish died (A) contained a large quantity of 

 algse and infusoria, and the pure water (B) had none. They 

 gave the following analysis : — 



A. B. 



Spec, grav fo24 ... 1-022 



Solids per cent 4-0780 ... 4"I095 



Ferric compounds per cent. ... o'llo6 ... 0^0724 

 Injurious organic matters ... ratio = 3 ... —Z 



Even on spectre copic analysis Mr. Endlich could not find in A 

 any mineral constituent which could noxiously affect the fish, 

 and he thinks that death must be caused by parasitic algse, while 

 Surgeon Glazier agrees with the prevalent opinion that the 

 ca'astrophe is due to the salt water being impregnated with 

 gases discharged from volcanic or geyser-like springs. During 

 November last the waters of Tampa, Sarasota, and Charlotte 

 Harbour were covered with thousands of dead fish, and the 

 stench was quite overpowering. 



The Blood of Insects. — Operating with the larva of Oryctes 

 nasicornis, M. Fredericq has observed [Bidl. Belg. Acad.) that 

 the blood of the animal, drawn off in a small glass cannula, is 

 a colourless liquid, but on exposure to the air presently takes a 

 decided brown colour, and coagulates. Ihe coloration he re- 

 gards as a purely cadaveric phenomenon. The substance which 

 becomes hrown is probably formed in the moment of coagulation, 

 and does not serve in the body as a vehicle between the external 

 air and the tis ues, like hamoglobin in Vertebrates and many 

 Annelids, luTmocyanin in Crustaceans, &c. \\'hen the larva is 

 ke, t a quarter of an hour in hot water (50° to 55°), the bleed 

 extracted does not coagulate or become brown. Once the sub- 

 stance which browns is produced, even a boiling temperature 

 does not prevent its browning. The biov\n substance once 

 formed is very stable, not being decomposed either by acids or 

 alkalies, and not made colourless by being submitted to vacuum 

 or kept in a closed vessel. The existence of an intermediary in 

 insects corresponding to haemoglobin M. Fredericq thinks very 

 problematical in view of the anatomical system, letting air pene- 

 trate into the heart of the tissues. 



New Pycnogonida. — The result of the examination of the 

 collection of Pycnogons made during the cruise of the U.S. 

 steamer Blake by Fdmund B. Wilson, has just been published as 

 No. 12, vol. viii. of the Harvard College Museum Bulletin. 

 This collection was found to possess features of considerable 

 interest, .'-nd though the species in it were few, some of thtm 



