HARDWICKE'S SCIENCE-GOSSIP. 



207 



ZOOLOGY. 



Repetitive Generic Names — A New Field of 

 Work. — There are, I doubt not, many among your 

 readers who, besides acquiring knowledge themselves, 

 would be glad to assist in the general advance of 

 science, but are deterred from attempting anything by 

 diffidence as to their powers, and ignorance as to the 

 direction in which they can best render service. To 

 such I would point out that there is an immensity 

 of work of the highest value to science, that only 

 requires time, intelligence, and perseverance. For 

 example, there are some 50,000 or 60,000 genera of 

 animals (recent and fossil), a dictionary of the names 

 of which, giving author, date, and class, is im- 

 peratively needed to prevent names now occupied 

 being attached to new, and it may be widely separated, 

 genera. The need of this may be shown by a few 

 examples (I could fill an entire number of Science- 

 Gossip with such) : — 



Aspis (Lawr.), 1768, Reptilia. 



Aspis (Germ.), 18 — , Coleoptera. 



Aspis (Treitschke), 1S29, Lepidoptera. 



Axia (Hiibn.), 1816, Lepidoptera. 



Axia (M. Edw.), 1837, Crustacea. 



Axia (Eschsch.), 1825, Acephala?. 



Axia (Lour.) is a plant-genus belonging to the 

 Valerianese. 



Lists of genera up to 186S have been published ; 

 these require to be combined into a single alphabetical 

 arrangement, and brought up to the present date, or, 

 say 18S0, inclusive. Funds for publication would 

 doubtless be forthcoming when the time arrived. 

 Any one willing to assist in the work of copying and 

 arranging is hereby requested to communicate with 

 IV. H. Dalton, H. M. Geological Survey, Weybread, 

 Harleston. 



Establishing A Rookery.— In your July 

 number, Mr. A. J. Robinson wishes to know how to 

 establish a rookery. Without wishing to dishearten 

 him, I fear he will find it rather a difficult problem. 

 Two gentlemen in this neighbourhood tried all kinds 

 of ways to induce the rooks to build, but without 

 success. In one case nests were made in the trees, 

 but the rooks still refused to come. The trees were 

 also covered with netting, and the rooks fed and kept 

 there ; still there was no result. In the other case, 

 the gentleman (a solicitor) tried all the means he could 

 to induce the rooks to build, but in vain. He left the 

 house some time afterwards, and the next tenant was 

 a clergyman ; then the rooks came at once and estab- 

 lished a fine rookery which increases every year. If it 

 is a likely place, Mr. Robinson and his friends might 

 get some young rooks and tame them, and clip one 

 wing to prevent them getting away— let them get well 

 accustomed to the place and they might build the follow- 

 ing season. I shall be glad to hear of any one having 

 succeeded. —J. Goodyear, Worsbrough, Barnsley. 



Simulation of Death by Insects. — What- 

 ever may be the case amongst the Coleoptera and 

 Arachnida, Mr. Slater's deductions, that the simula- 

 tion of death is as a rule confined pretty much to 

 those insects whose flight is weak and movements 

 slow, will not hold good as regards the Lepidoptera. 

 In no insect is the habit of feigning death more con- 

 spicuous than in that interesting little family of moths 

 — the Hepialidre, all of them characterised by a very 

 rapid flight, and on account of which the English name 

 of " swift " has been attached to them. I cannot 

 agree with the writer of the paper to which Mr. 

 Slater refers, that the practice of shamming death is 

 not to be regarded as a stratagem to escape danger, 

 all my observations tending to prove to my own mind 

 that it is. I have frequently amused myself by 

 catching numbers of swifts m order to watch their 

 actions, and have from time to time taken all the five 

 species commonly. There was no trouble in ' ' boxing " 

 them when once you had caught them, as their in- 

 variable habit is to adopt the " death dodge " and fall 

 helplessly to the bottom of the net ; but take them 

 out and place in the palm of the hand, or put them 

 into the chip box, and leave the lid off, and you will 

 not have to wait many seconds before the little 

 impostors are " off like a shot," laughing, perhaps like 

 some begging human impostors afflicted with tempo- 

 rary lameness, blindness, and other maladies, at your 

 credulity. All the Hepialidse emit a peculiar odour 

 which clings to the boxes in which they have been 

 confined for some few minutes after they have been 

 turned out ; probably it acts as a further protection 

 against certain foes. — Joseph Anderson, Chichester. 



Mimicry in Insects. — The following case of 

 protective mimicry in Pyrameis Cardui may be of 

 interest to your readers. The paths of my garden are 

 covered with fine shingle from the beach, and recently 

 I noticed a number of painted lady butterflies 

 {Pyrameis Cardui) hovering over one of the paths, occa- 

 sionally settling on it. In order to notice them more 

 closely, I moved up close to where I had seen one settle, 

 but could not distinguish it until I almost trod on it, 

 when it rose and flew a short distance, and again settled 

 on the path with the wings closed, in which position, 

 from the mottled underside of the wings so closely 

 resembling the colour of the shingle, it was not easy 

 to detect. After remaining quiet for a few minutes it 

 slowly opened its wings, and then sat fanning itself 

 after the fashion of the Vanessidse. — Charles Foran. 



Ancylus Lacustris Floating. — The British 

 Ancyli or fresh-water limpets do not as yet appear to 

 have been seen floating, for Jeffreys, in his "British 

 Conchology " mentions that they " have never been 

 observed in a floating position " (vol. i. page 119). But 

 I am able to assert that I have watched two, out of 

 fourteen specimens, making their way in such a 

 position on the under-surface of the water, with shell 

 downwards, as is the case with other Limnreada?. 



