,20 



NATURE 



[February 4, 1892 



tinct. When it was absent, dark lines, following the direction 

 of the lateral axes, were visible in some cases. Frequently an 

 indistinct striation was present. Gilbert Rigg. 



Manchester Museum, Mineralogical Department, 

 January 12. 



A Tortoise inclosed in Ice. 



I SHOULD like to be allowed to record a case of a water-tortoise 

 surviving an incarceration in ice, somewhat similar to that given 

 in Nature (vol. xliv. p. 520). 



In this instance, the tortoise has hibernated in a stone basin, 

 in which there were about 6 inches of water and a quantity of 

 dead leaves. The whole was, I believe, frozen into a solid 

 mass. At any rate, when, on December 29, I examined 

 a cake of ice and leaves, from 2 to 3 inches thick, which was 

 floating in the basin after a thaw, I found the tortoise with its 

 back embedded in the under side of the mass, and with nearly 

 2 inches of porous-looking ice above it. The animal, though 

 torpid, was alive, and I replaced it in the basin. Later on it 

 put its nostrils up to the surface, and two days afterwards was 

 seen with its head out of the water as usual. It remained in 

 the pond, which has been again frozen over, in less than a week 

 after this observation. Frank Finn. 



31 Walton Crescent, Oxford, January 22. 



Alpine Rubi. 



In a footnote in Nature (vol. xlv. p. 10) it is stated that 

 " The two highest-known species of Rubtis are pinnattts and 

 rigidus, at 5000-6000 feet." This is hardly correct, unless it 

 is intended to refer to African species only. In South America, 

 R. megallococctis, R. boliviensis, R. bo<;otensis, and A', roseus 

 occur at 8000 feet, and R. rusbyi at 10,000. In Colorado I 

 have found R. strigosus above 10,000 feet (see Bull. Torrey Bot. 

 Club, 1890, p. 10 ; 1891, p. 169). In the Indian region, R. 

 ellipticus goes to 7000, R. lasiocarpus to 8000, and R. bijiorus 

 and R. rosif alius to 10,000 feet. 



The name of the wild Zca is Z. canina, Watson (local name, 

 " mais de coyote"), not nana, as given in Nature, vol. xlv. 

 p. 39. T. D. A. COCKERELL. 



Institute of Jamaica, Kingston, Jamaica, 

 December 30, 1891. 



UTILIZATION OF HOMING PIGEONS. j 



T^HE utilization of the homing instinct of the domes- j 

 •'- ticated varieties of the blue rock pigeon, the 

 Columba Hvia, for military purposes, has been effected by 

 /most of the Governments in Europe. In France, Ger- 

 many, Austria, Switzerland, Italy, Spain, and Portugal , 

 the organization has been very complete. It has even 

 extended to Russia, Denmark, and Sweden ; and Africa 

 has been brought into communication with Spain by 

 stations at Ceuta and Mellila. England alone, of all the 

 great Powers, has neglected this important mode of com- 

 munication, which is available under circumstances that 

 preclude the employment of any other means. 



It cannot be said that they have not been brought under 

 the notice of the military and naval authorities. Nearly 

 twenty years ago, on the occasion of the despatch of a 

 flight of seventy-two birds from the Crystal Palace to 

 Brussels, when the first birds arrived before the telegram 

 which was sent to announce their departure, I wrote a 

 letter to the Times of June 27, 1873, calling attention 

 to their utility, and asking the question : " What would be 

 the value of the birds, in the event of a war in which we 

 may be engaged, that would convey messages to or 

 from Guernsey, Jersey, and other places, when the sub- 

 marine wires had been cut by the enemy ? " ; and in a 

 lecture delivered by me before the Royal Engineers' 

 Institute at Chatham, on the use of pigeons for military 

 purposes, I entered at some length into their mode of 

 training and general utilization. 



The employment of the Columba livia depends upon 

 several conditions which are not without interest. In 



j the first place, this species is one of the comparatively 

 j few capable of domestication, a faculty which is totally 

 I distinct from, though frequently confounded with, the 

 facility of being tamed. A domesticated animal is 

 , attached to its home, and returns to it of its own will ; a 

 tame animal is merely familiar with man. These two 

 I states are admirably illustrated in the closely allied 

 species, the fowl and the pheasant. Both were originally 

 I perfectly wild, but when domesticated the chickens in- 

 variably return home to roost, while the pheasants, 

 though descended from numberless generations of birds 

 bred in confinement, have no attachment whatever to 

 j the place of their birth or rearing. 



I In its natural habitat (the rocky cliffs of the sea-shore) 

 j the blue rock pigeon has to fly long distances in search 

 of food, which, when breeding, it stores up in its crop 

 I and carries home to its young. This necessitates strong 

 ! powers of flight and well-developed perceptive faculties, 

 j it being guided in its return solely by sight, and not, as 

 is often supposed, by any special instinct. 



The pigeons that are used for carrying messages are 

 i bred solely for that purpose. A process of artificial 

 j selection, as rigorous and remorseless as that of nature, 

 j is followed. The young birds, after acquiring their 

 power of perfect flight, and learning the contour of the 

 I country in their circuits around their home, are taken in 



the direction in which it is desired that they should fly, 

 and trained stage after stage until they know every 

 locality over which they have to traverse. This training 

 is absolutely necessary, if their return home is to be 

 depended on. During its performance the inferior birds, 

 those whose intelligence and determination are not well 

 developed, are lost ; and the best birds, only, retained. 

 This loss, in the long-distance flights which are flown by 

 the Belgians and by the best homing pigeon societies in 

 England, is very severe. Old birds, that know large 

 tracts of country well, may be taken in new directions, 

 provided they are not too extended, with safety, but 

 young birds that have not been trained would almost 

 certainly be lost if carried many miles from their home. 



Every homing pigeon flyer recognizes the hereditary 

 character of this acquired faculty, and will give a very 

 high price for birds descended from parents that have 

 flown long distances, whereas he would not purchase 

 another bird of precisely similar appearance were he not 

 acquainted with the performances of its ancestors. The 

 fancy varieties of pigeons, especially those which are 

 called carriers in England, are perfectly useless for the 

 purpose of flying distances. 



The birds that are most valued are almost all descended 



NO. I 162, VOL. 45] 



