July 24, 1879J 



NATURE 



291 



tropical sun, the black lizards being therefore most conspicuous. 

 Prof. Peters, of Berlin, to whom some years ago I sent specimens 

 of these reptiles, called them in one of his letters Cnemidophorus 

 nigricolor, but as I am not aware of his having published this 

 name, I believe he got soon convinced of its true character as a 

 melanotic variety. I may be allowed to add that I have men- 

 tioned this case already in my " Estudios sobre la Flora y Fanna 

 de Venezuela" (Caracas, 1877), pp. 280, 281, when lalso pointed 

 out the difficulty of its explanation by the " struggle for exist- 

 ence " theory. A. Ernst 

 Caracas, May I J 



Intellect in Brutes 



1. The following case was witnessed by my friend Dr. Rafael 

 Villavicencio, of Caracas, during his stay last year in the town 

 of Ponce, in the Island of Portorico : — 



The little river in the neighbourhood of the town had risen, in 

 consequence of heavy rains, and ran with rather considerable 

 swiftness. In a certain place it is crossed by a road, where it 

 was forded by a countryman sitting on his mule carl. His dog 

 swam after him, but was taken down by the current and carried 

 back to the bank. Then, after a moment's hesitation, the 

 animal ran some distance up the bank, jumped into the water, 

 and managed to reach the other side just where the road 

 'emerged from tlie river, acting thus precisely as a boatman might 

 have done in similar circumstances. 



2. To my friend Dr. Velasquez Level, a respectable physician 

 of this city, and for several years a resident of the Island of 

 Margarita, I am indebted for the follo%ving touching instance of 

 the sagacity of a bitch. Her owner, for some reason or other, 

 had destroyed all the female puppies in two successive litters. 

 On her having brought forth a third one it was found that there 

 were but three male puppies. The bitch, however, was observed 

 to leave her whelps occasionally, and to return some time after. 

 Being followed, she was discovered suckling three female puppies, 

 which she had hidden under some brushwood, undoubtedly with 

 the intention of saving them from the master's cruel hands. This 

 case happened in a small place, called Juan Griego, on the 

 northern side of the island. A. Ernst 



Caracas, May 15 



Intellect in Brutes — a Cat and a Mirror 



Many years ago at Came farmhouse, where relatives of mine 

 were then living, the household cat was observed to enter a bed- 

 room ill course of being spring-cleaned. 



The looking-glass being on the floor the cat on entering was 

 confronted with its own reflection and naturally concluded that 

 he saw before him a real intruder on his domain. 



Hostile demonstrations were the result, followed by a rush to 

 the mirror and then meeting an obstacle to his vengeance, a 

 fruitless cut round to the rear. This manoeuvre was more than 

 once repeated with of course equal lack of success. Finally the 

 cat was seen to deliberately walk up to the looking-glass keeping 

 its eyes on the image, and then when near enough to the edge, 

 to feel carefully with one paw behind, for the supposed intruder, 

 whilst with its head twisted round to the front it assured itself of 

 the persistence of the rellection. 



The result of this experiment fully satisfied the cat that he had 

 been the victim of delusion and never after would he condescend 

 to notice mere reflections, though the trap was more than once 

 laid for him. Thos. B. Groves 



Butterfly Swarms 

 Even yotir varied correspondence from all parts of ihe world 

 has rarely furnished us with such a wonderfully complete and 

 interesting personal observation as that of Mr. Sydney B J 

 Skertchly (Nature, vol. xx. p. 266) on the West African 

 breeding-grounds of Vanessa carJiii, and the almost mechanical 

 impulse and simultaneity with which such a swarm as that which 

 he describes free themselves from the pupa-case and set forth on 

 their migration. Can any one throw a similar light on the 

 periodicity of Cclias edtisa? V. cardui is a more constant 

 insect in this neighbourhood than any other with which I am 

 acquainted ; but the numbers in June of this year were quite 

 unusual. Also we remarked that they were very high-coloured 

 and vigorous, unlike the ordinary washed-out hybernated speci- 

 mens of early summer. As one of your correspondents has 



remarked of his neighbourhood, so here C. edusa swarmed in 

 1877. It was the prevailing insect. In 1878 we had hardly a 

 solitary example. The so-called C. hdice — the pale variety of 

 C. edusa — was frequent in 1877. I saw none of C. hyale ; in- 

 deed, have never seen that insect here. Henry Cecil 

 Bregner, Bournemouth 



REPORT OF AN UNUSUAL PHENOMENON 

 OBSERVED AT SEA 



'T'HE following Report to the Admiralty has been com- 

 -•■ municated to us for publication by Capt. Evans, 

 C.B., F.R.S., the Hydrographer to the Navy : — 



H.M.S. Vultu7-c, Bahrein, May 17, 1879 

 Sir, — I have the honour to inform you that, at about 

 9.40 P.M. on May 15, when in lat. 26° 26' N. and long. 

 53° 11' E., a clear, unclouded, starlight night, Arcturus 

 being within some 7° of zenith, and Venus about to set ; 

 wind north-west, force 3, sea smooth, with slight swell 

 from the same direction ; ship on starboard tack, heading 

 west-south-west and going three knots, an unusual phe- 

 nomenon was seen from the vessel. 



I noticed luminous waves or pulsations in the water, 

 moving at great speed and passing under the ship from 

 the south-south-west. On looking towards the east, the 

 appearance was that of a revolving wheel with centre on 

 that bearing, and whose spokes were illuminated, and 

 looking towards the west a similar wheel appeared to be 

 revolving, but in the opposite direction. I then went to 

 the mizen top (fifty feet above water) with the first lieu- 

 tenant, and saw that the luminous waves or pulsations 

 were really travelling parallel to each other, and that 

 their apparently rotatory motion, as seen from the deck, 

 was caused by their high speed and the greater angular 

 motion of the nearer than the more remote part of the 

 waves. The light of these waves looked homogeneous, 

 and lighter, but not so sparkling, as phosphorescent 

 appearances at sea usually are, and extended from the 

 surface well under water ; they lit up the white bottoms 

 of the quarter-boats in passing. I judged them to be 

 twenty-five feet broad, with dark intervals of about 

 seventy-five between each, or 100 from crest to crest, 

 and their period was seventy-four to seventy-five per 

 minute, giving a speed rouglily of eighty-four English 

 miles an hour. 



From this height of fifty feet, looking with or against 

 their direction, I could only distinguish six or seven 

 waves ; but, looking along them as they passed under the 

 ship, the luminosity showed much further. 



The phenomenon was beautiful and striking, com- 

 mencing at about 6h. 3m. Greenwich mean time, and 

 lasting some thirty-five minutes. The direction from 

 which the luminous waves travelled changed from south- 

 south-west by degrees to south-east and to east. During 

 the last five minutes concentric waves appeared to 

 emanate from a spot about 200 yards east, and these 

 meeting the parallel waves from south-east did not cross, 

 but appeared to obliterate each other at the moving point 

 of contact, and approached the ship, inclosing an angle 

 about 90°. Soundings were taken in twenty-nine fathoms; 

 Stiffe's Bank, with fifteen to twenty fathoms, being west 

 about one mile. The barometer was already at 29"2S 

 from 8 to 12 p.m. 



At 8 P.M. 10.15 P.M. Midnight. 

 Temperature of air ... 84 ... 83 ... 83 



Temperature of sea- water ... 84 ... 82 ... 82 



I observed no kind of change in the wind, the swell, or 

 in any part of the heavens, nor were the compasses dis- 

 turbed. A bucket of water was drawn, but was unfortu- 

 nately capsized before daylight. The ship passed through 

 oily-looking fish spawn on the evening of the I5lh and 

 tnorning of the 16th inst. — I have the honour to be. Sir, 

 your obedient servant, 



J. Eliot Pringle, Commander 



