348 



NA TURE 



[February 7, 1901 



The Mongoose in Jamaica. 



In Jordan and Kellogg's admirable little book, " Animal 

 Life," we read (p. 293): — "The mongoose, a weasel like 

 creature, was introduced from India into Jamaica to kill rats 

 and mice. It killed also the lizards, and thus produced a 

 plague of fleas, an insect which the lizards kept in check." 



As it is evident from this and other signs that the Jamaica 

 mongoose is to become celebrated in text-books, it seems worth 

 while to call attention to the facts actually known about it. An 

 excellent summary showing the status of affairs in 1896 was 

 written by Dr. J. E. Duerden and published in ihs Journal oi 

 the Institute of Jamaica, vol. ii. pp. 2'<8-29i. In the same 

 volume, p. 471, are further notes on the same subject. 



The creatures which increased and became a pest were ticks; 

 not fleas. The present writer can testify to their excessive 

 abundance in the island in 1892 and 1893. The species were 

 various, and were examined by Marx and Neumann, whose 

 determinations appear in Joitrn. Inst. Jamaica, vol. i. p. 380, 

 and vol ii. p. 470. It will be noted that the common species 

 are not confined to Jamaica, and, in fact, have probably, most of 

 them, been introduced from elsewhere. Hence it is quite 

 possible that their abundance is in large part due to their recent 

 introduction. T. D. A. Cockerell. 



East Las Vegas, New Mc-cico, U.S.A., January 17. 



Thermochemical Relations. 

 Let us consider gr. 2 of H, gr. 16 of O and gr. 71 of CI, 

 namely, volumes 2 of H, i of O, 2 of CI. We can combine 

 these corps two by two to form the three following 

 compounds : — 



gr. 87 of CI2O gr. 18 of H2O gr. 73 of HCl 



that occupy respectively 2, 2, 4 volumes. 



The heats of combination are respectively : — 



-14 +58 +44, 



between which is the simple relation 



- 14 + 58 = 44. 



In another example, where one of the components is solid 

 but remains the same ratio between the volumes of the com- 

 pounds, we have again the same relation between the combining 

 heats. In fact, with 



gr. 2 of C gr. 4 of H gr. 32 of O 



we can form 



gr. i6of CH4 gr. 44 of CO, gr. 36 of HoO 



which occupy respectively 2, 2 and 4 volumes. 

 The combining heats are respectively 



+ 19 +97 -H16, 



and we find 



19 f 97 = 116. 



Is it a casual coincidence or a law ? 



Spezia (Italy), Nov. 14, 1900. Carlo Del Lu.N(,o. 



Direction of Spirals in Horns. 



About Mr. Blanford's interesting remarks on my letter in 

 Nature for January 10, I should like to answer that, far from 

 thinking the matter " simple," I find that the facts are nowhere 

 recorded and certainly are not generally known to naturalists 

 or sportsmen. This is why I attempted to formulate rules. 



The rule that in antelopes the direction of the spiral is 

 "crossed " {i.e., the right horn is sinistral, and the left horn is 

 dextrorsal) holds good in the Koodoos, Elands, Indian ante- 

 lope, Bushbuck, Impalla, and Speke's antelope (noted by me in 

 the Lancet, January i, 1898, " On Spiral Growth"). 



In oxen the horns are "homonymous" in direction — the 

 right horn twists to the right, the left horn to the left — and 

 many horns show a good spiral. I may mention the Cape 

 buffalo, musk ox, domestic ox, also the Urus and the Chartley 

 bull. The only exception to the rule in the Cambridge Museum 

 is an Indian buffalo. 



In the sheep, the direction of the spiral is " homonymous," as 

 in the ox, except Ovis orientalis and OiJis nahura. 



In the goats, Mr. Blanford, in his " Fauna of British India, 

 Mammalia," notes that there is a difference between the wild and 

 the lame goats in the following passage: "But the spiral in 

 tame goats is almost always in the reverse direction to that 



NO. 1632, VOL. 63] 



found in Markhor, the anterior ridge in the tame animals turning 

 inwards at first in each horn 



" I have, however, seen exceptions ; there is one from Nepal 

 in the British Museum." 



After searching many books on horns (including Mr. 

 Lyddeker's), this is the only note on the direction of spirals 

 that I can discover. The causes of the spirals, and of the 

 differences in directions, are still to seek. 



Cambridge. George Wherry. 



SOME DISPUTED POINTS I,V ZOOLOGICAL 

 NO.MENCLA TURE. 



A MON(i that large section of the general public who 

 "'*- are interested, to a greater or less degree, in 

 natural history there is a widely spread impression that, 

 as most of the more familiar animals have a single, 

 definite and indisputable popular designation, so every 

 known species in the animal kingdom has one proper 

 technical title by which it is known throughout the zoo- 

 logical world ; and consequently that when they have 

 once made themselves acquainted with this title, there is 

 no more to be said on the subject. To a certain limited 

 extent (some authorities would, perhaps, be inclined to 

 say invariably) there is no doubt that this idea is per- 

 fectly well founded. But, in the first place, there is a 

 difference of opinion among zoologists as to the limits of 

 genera, and whereas one worker would retain a species 

 in the genus in which it was placed by its original de- 

 scriber, another would regard it as entitled to represent 

 a genus by itself. Thus one great element of diversity 

 in nomenclature is introduced. 



But there are also a very large number of cases in 

 which an equal diversity of view obtains as to the proper 

 specific title of an animal. And the inquirer will not be 

 long in ascertaining that, in place of unanimity, an almost 

 chaotic state of uncertainty prevails as to what should be 

 the proper binomial designation of a large percentage of 

 animals. Consequently, in place of being one of the 

 easiest, the question of nomenclature is, in many cases, 

 one of the most difficult ; and the unhappy inquirer will 

 too often find that he receives a different answer from 

 almost every authority to whom he applies. Nor is this 

 all, for whereas a considerable nuinber of systematic zoo- 

 logists are agreed in some measure upon certain general 

 principles of nomenclature, their opinions are not shared 

 by many of the workers in palaeontology, morphology 

 and geographical distribution, who adhere to more anti- 

 quated views on these questions. 



The reasons for this regrettable and unfortunate state 

 of affairs are many and varied. And as a crisis on the 

 question is likely to arise in the near future, if indeed it 

 be not already upon us, the editor is of opinion that 

 there are many readers of Nature who would like to be 

 informed of some of the chief points at issue, and of the 

 more important suggestions which have been made 

 towards arriving at a settlement. It will consequently 

 be understood that the present article has been written 

 solely from this point of view, and that it inakes no 

 pretence to discuss all the questions, or to enter into 

 details interesting to zoologists alone. 



One of the points at issue — and it is one of the most im- 

 portant — is what we may term the theory of the sacredness 

 and immutability of the specific name. Soon after Linnseus 

 had completed the last edition of the " Systema Naturas " 

 published under his own personal supervision, it became 

 apparent that a large number of the animals named by 

 him could no longer be permitted to remain in the genera 

 in which they were included in that work. The giraffe, 

 for example, which had been named Cervus catnelo- 

 pardalis by the Swedish naturalist, was certainly entitled 

 to generic distinction from the deer. At this date the 

 idea of the "sacredness" of the species name had not 

 yet originated, and Gmelin, in his edition of the 



