544 



NATURB 



[October 2, 1890 



an absolute desert. In an ordinary summer's afternoon walk at 

 home one sees more species of plants in flower than I have seen 

 since we entered the river. . . . However, this may improve, as 

 it is now the dead of winter here, and with the advent of spring 

 T hope to see many new and interesting flowers appear. Zoo- 

 logically, too, it is disappointing, except in the case of birds. 

 In the lower parts of the river not a bird was to be seen, but 

 now they are rather more frequent, and I have already observed 

 116 species, of which I believe about 30 have not before been 

 collected in Argentina. Owing to the desert nature of this part 

 of the Chaco, its human inhabitants are very few, scattered, and 

 nomadic. We have not seen a single Indian or canoe on the 

 Pilcomayo. But we know they are about, for nearly every day 

 we see their great fires for hunting all around us, and we occasion- 

 ally come across a chipped palm, or the remains of an old tolda, 

 the rude shelter which serves them as a tent ; now and again, 

 too, we see a human footprint, sometimes of immense 

 size, impressed upon the muddy margin of a lagoon. So we 

 are always on the alert, the four Britons of the Expedition 

 keeping watch at night, fully armed and wide awake. 

 The four said Britons are Poole, Kenyon (English), Henderson 

 the chief engineer, and myself. When I go away collecting 

 also, as I do every day, I always go with loaded revolver and 

 knife— ready for emergencies. For in addition to Indians there 

 are abundance of tigers about, which one has to be prepared for. 

 Yesterday- we got an alligator close to the boat, 8 feet long. 

 The alligators here are all small, 8 feet being the largest we 

 have seen. ... 



"As regards food we are on very short rations, being within- 

 a month or so of the end of our provisions. The canoe is to be 

 sent down soon, I believe, to hurry up the fresh supplies of pro- 

 visions, and by it I shall send this letter, although it is very 

 doubtful whether you will ever get it. The health of the men 

 is not good ; we have always two or three of the 17 on board ill. 

 I have, however, had excellent health. The only thing dis- 

 agreeable is the fearful cold. In the mornings the thermometer 

 is often nearly at freezing-point, and I feel quite benumbed. 

 Fortunately, it generally gets a little warmer during the day, the 

 temperature rising in the afternoon to between 70° and 90° F. 

 The river- water is regular brine here, quite as salt as sea- water, 

 and when occasionally we run out of fresh water for a few days, 

 it is very disagreeable having to take coffee, &c. , made with the 

 salt water. Of fruits here, there are none worth eating. The 

 young parts of the palm-trees are eatable, and we use a good 

 deal of it in order to economize the rice, &c. I don't expect at 

 all that we can possibly reach Bolivia, and I don't think the 

 river could ever be made navigable." 



Protective Colours. 



Mr,Poulton, in his book entitled "The Colours of Animals," 

 seeking a reason for the glistening metallic colours of many 

 chrysalides, after showing that the colour is probably protective 

 in its origin, states "that it has arisen from the protective re- 

 semblance to rough dark surfaces of rocks." 



He comes to this conclusion after failing to find other more 

 probable examples of glistening bodies in nature. 



Are such not, however, very common (i.) in the slime or mucous 

 covering many of the Invertebrata, and which snails and slugs 

 leave on all surfaces over which they have passed ; (ii.) the webs 

 of spiders and their allies, especially if moist ; (iii.) the exudation 

 or excretion of many plants ; (iv.) decomposing bodies ; (v.) the 

 bark of many trees ? 



Perhaps the commonest places to find glistening chrysalides 

 are on palings, tree trunks, and various plants ; all of which 

 structures are usually resplendent with one or more of the above 

 metallic hues, and among which the chrysalides are very hard to 

 find. 



May not these more common objects be those of attempted 

 resemblance, rather than the less frequent pieces of broken rock ? 



Grosvenor Club, Bond Street, W. Walter K. Sibley. 



Mr. Sibley's letter appears to me to contain valuable sugges- 

 tions as to the meaning of the metallic appearance of certain 

 chrysalides. It is probable that a resemblance to the objects he 

 suggests does aid in concealing the pupse. Mr. Roland Trimen 

 has similarly concluded that certain brilliant beetles {Cassididce) 

 are protected by resembling drops of dew. At the same time I 

 think that there is some evidence that the metallic appearance of 



NO. 1092, VOL. 42] 



the pupae of Vanessida may have been originally acquired in order 

 to favour concealment against glittering mineral surfaces. The 

 evidence is as follows :— (l) In shape and character of the surface 

 these pupee strongly resemble a rough and broken piece of rock. 

 (2) They appear in two forms, resembling grey and weathered as 

 well as freshly exposed and glittering rock surfaces. (3) When 

 they seek green leaves for pupation they either conceal them- 

 selves with the greatest care {V. atalanta), or a glittering variety 

 of other species is represented by a green variety which is in- 

 conspicuous against the leaves (F. lo). (4) Another species 

 ( V. tirtica), which lacks the habit of V. atalanta and the green 

 variety of V. lo, is, as far as my experience goes, very rarely 

 found on the leaves of its food- plant, and when so found, is, as 

 a rule, diseased. 



I mention the chief lines of evidence upon which I have relied 

 in order to show that it was not merely the failure " to find other 

 more probable examples of glittering bodies in nature " which 

 led me to adopt the view alluded to by Mr. Sibley. Although 

 I still consider that my hypothesis is probable, at any rate for 

 the VanessidcB, I am convinced that the resemblance to other 

 glittering objects, such as those mentioned by Mr. Sibley, has 

 favoured the development and especially the persistence of the 

 metallic appearance. . ; E. B. PoULTON. 



, September 19. 



The Aryan Cradle-land. 



" It will be for the benefit of our science," said the President 

 of the Anthropological Section of the British Association, "that 

 speculations as to the origin and home of the Aryan family 

 should be rife ; but it will still more conduce to our eventual 

 knowledge of this most interesting question if it be consistently 

 borne in mind that they are but speculations." With the 

 latter, no less- than with the former opinion, I cordially agree. 

 And as, in my address on the Aryan cradle-land, in the 

 Anthropological Section, I stated a greater variety of grounds in 

 support of the hypothesis of origin in the Russian steppes than 

 has been elsewhere set forth, I trust that I may be allowed 

 briefly to formulate these reasons, and submit them to discussion. 



(i) The Aryans, on our first historical knowledge of them, 

 are in two widely separated centres, Transoxiana and Thrace. 

 To Transoxiana as a secondary centre of dispersion the 

 Eastern Aryans, and to Thrace as a secondary centre of 

 dispersion the Western Aryans, can, with more or less clear 

 evidence, or probable inference, be traced, from about the 

 fourteenth or perhaps fifteenth century B.C. ; and the mid- region 

 north-west of Transoxiana and north-east of Thrace — and which 

 may be more definitely described as lying between the Caspian 

 and the Euxine, the Ural and the Dnieper, and extending from 

 the forty-fifth to the fiftieth parallel of latitude — suggests itself as 

 a probable primary centre of origin and dispersion. 



(2) For the second set of facts to be considered reveal earlier 

 white races from which, if the Aryans originated in this region, 

 they might naturally have descended as a hybrid variety. Such 

 are the facts which connect the Finns of the north, the Khirgiz 

 and Turkomans of the east, and the Alarodians of the south, 

 with that non-Semitic and non-Aryan white stock which have 

 been called by some Allophyllian, but which, borrowing a term 

 recently introduced into geology, may, I think, be preferably 

 termed Archaian ; and the facts which make it probable that 

 these white races have from time immemorial met and 

 mingled in the South Russian .steppes. Nor, in this connection, 

 must the facts be neglected which make great environmental 

 changes probable in this region at a period possibly synchronous 

 with that of Aryan origins. 



(3) In the physical conditions of the steppes characterizing 

 the region above defined, there were, and indeed are to this day, 

 as has been especially shown by Dr. Schrader, the conditions 

 necessary for such pastoral tribes as their language shows that 

 the Aryans primitively were ; while, in the regions between the 

 Dnieper and the Carpathians, and between the Oxus and the 

 Himalayas, the Aryans would, both in their south-western and 

 south-eastern migrations, be at once compelled and invited, by 

 the physical conditions encountered, to pass at least partially 

 from the pastoral into the agricultural stage. 



(4) The Aryan languages present such indications of hybridity 

 as would correspond with such racial intermixture as that sup- 

 posed ; and in the contemporary language of the Finnic groups 

 Prof, de Lacouperie thinks that we may detect survivals of a 

 former language presenting affinities with the general character- 

 istics of Aryan speech. 



