IIARDWICKE'S SCIENCE-GOSSIP. 



277 



the object of this immersion is to ensure the entire 

 destruction of the cellulose, when the valves after 

 repeated washing are then burnt on the cover at a 

 dull red heat until perfectly white. The cover being 

 allowed to get cold a drop of oil of lavender is 

 placed on it. Mr. Petit, after many experiments with 

 different mediums, has found that this oil is the only 

 one that penetrates thoroughly the valves, such as 

 Melosira nicmmularia, M. arenaria, &c. A drop of 

 Canada balsam being then put on the glass slip, 

 the cover is placed on it and the whole warmed over 

 the lamp to evaporate the oil of lavender and partly 

 harden the balsam. In order to show on the same 

 slide the different views of the valves, Mr. Petit 

 adds to those in situ a little portion of the gathering 

 prepared in the ordinary way, viz., by boiling in acid. 

 The preparations thus obtained are perfect and most 

 interesting. — J. Tempere. 



ZOOLOGY. 



The Guinea Pig. — As I find that no work on 

 Natural History I have consulted gives the correct 

 period of gestation in the guinea pig, I think it might 

 be interesting for me to record my observations. 

 Eighteen instances I have carefully watched, and I 

 find, without any exception, that the time is sixty-six 

 days. As the guinea pig breeds again on the same 

 day that it brings forth its young, and also, as I can 

 testify, at the early age of eighty days, this no doubt ac- 

 counts for the reason why a less time for gestation has 

 been recorded in works on Natural History than is 

 the fact. In no instance have there been more than 

 four at a birth. — Frederick Gull. 



Butterflies and Coloured Nets. — At Men- 

 tone, in 1S78, I was at first utterly unable to catch 

 any specimens of the beautiful Cleopatra butterfly. I 

 had a light net with a blue tarlatan bag and each 

 time I missed a specimen, it flew away to a great 

 distance. It was also very rarely that one came 

 within reach of my net. On mentioning this to a 

 friend, he told me he found them very easy to catch, 

 as they seemed to follow his net, the bag of which 

 was green. Upon hearing this, I adapted a green 

 bag to my insect net, and found it was only necessary 

 to wave it backwards and forwards, when one or 

 more Cleopatras would be sure to come and try and 

 settle on it, and were easily captured. After I had 

 thus procured plenty of specimens, I was one day 

 hunting for the beautiful Anthocharis Eupheno when 

 a Cleopatra fluttered after my net and could not be 

 got rid of. And yet this was in a hot lemon planta- 

 tion, with the green leaves of the lemon trees above 

 and below. Again when driving from Salerno to 

 Palestrina last spring, I had my net with the green 

 bag. I saw a Cleopatra flying towards the carriage, 

 and on waving my net behind, it followed for some 

 distance. Mr. W. S. Coleman states that Gonepteryx 



Rhamni and Cleopatra have been proved identical^ 

 since both have been reared from the same batch of 

 eggs. The female Cleopatra does not differ visibly 

 from G. Rhamni and was not attracted by green. This 

 insect has often been labelled as a distinct species, 

 Gonepteryx Cleopatra, and at the museum at Florence 

 was labelled " Colias Cleopatra," while the ordinary 

 brimstone butterfly was labelled Gonepteryx Rhamni, 

 thus erroneously putting two varieties of the same 

 species into separate genera ! The male only differs 

 from our British variety in having the fore wings 

 nearly entirely suffused with bright orange colour in- 

 stead of its being limited to a spot the size of a pin's 

 head. Naturally therefore, as soon as possible, I 

 tried waving my green net in a field full of the ordi- 

 nary Rhamni, but none of them took any notice of it. 

 Sometimes, when one settled, I waved my net close 

 to it, but it either remained where it was, or else 

 invariably flew right away. "Why one variety of a 

 butterfly is attracted by green, and the other with 

 which it is identical should pass it by unheeded, 

 seems to me wholly incomprehensible. It would 

 however be highly interesting if any of the readers of 

 Science-Gossip who had the opportunity were to try 

 whether this beautiful variety is attracted by any 

 other colour (say yellow), or to notice whether any 

 other insects are attracted by certain colours in a 

 similar manner. — G. H. Bryan. 



The Fauna and Flora of the Cuckmere 

 District.— Mr. F. C. S. Roper's last paper read at 

 the Eastbourne Natural History Society was a very 

 important one, dealing with the additions to the Fauna 

 and Flora of the above district during the past year. 



"The Fauna of Norfolk." — This well-known 

 book, written thirty years ago by the Rev. Richard 

 Lubbock, M.A., now appears as a new edition pub- 

 lished by Jarrold & Co. : London and Norwich. In 

 addition to the intrinsic merits of the book, of which 

 we can personally speak in the superlative degree as 

 one of the most pleasantly written of the many 

 pleasant natural history books our language is so rich 

 in, describing as it does the "Broad District "—a 

 country unlike any other part of England, and a very 

 paradise to the botanist, entomologist, and orni- 

 thologist — this new edition is edited by Mr. Thomas 

 Southwell, the active secretary of the Norfolk and 

 Norwich Naturalists' Society, whose full and 

 accurate knowledge of the natural history of Norfolk 

 better fits him for the task than any other man we 

 know of. The memoir of Mr. Lubbock is written by 

 Henry Stevenson, F.L.S., author of the " Birds of 

 Norfolk," and Professor Alfred Newton contributes 

 an appendix on Hawking in Norfolk, &c. Many 

 other naturalists, such as Mr. J. H. Gurney, Mr. 

 C. G. Barrett, Dr. Lowe, of Lynn, Mr. H. D. Gel- 

 dart, &c, have also contributed notes or other 

 assistance. We are glad to see an old and valued 

 friend appearing in such good company. 



