BARDWICKE'S SCIENCE-GOSSIF. 



"3 



The Eleventh Annual Exhibition of the S. London 

 Entomological Society, was held at the Bridge House 

 Hotel, London Bridge, S.E., on Wednesday, the 

 15th ult., and was continued on the Thursday 

 following from I P.M. 



MICROSCOPY. 



Preservation of Melicerta Ringens. — Last 

 May you inserted a paragraph bearing the above 

 heading, in which I narrated how I had preserved 

 in captivity this organism for twelve months without 

 any interregnum. I have to-day to recount a further 

 success in this matter. During the last year I have 

 never been without numbers of this rotifer ; at the 

 present time I have very many. Only once have I 

 feared that I might lose this attractive creature 

 altogether, and this was on my return home last 

 October, after my autumn holiday. I found during 

 my absence that certain juvenile members of my 

 family, out of the overflowing kindness of their 

 hearts, had fed the sticklebat with pieces of biscuit 

 as large as hazel nuts, and the plants, too, had been 

 permitted to grow unpruned ; consequently, on my 

 return, I found the whole aquarium exceedingly 

 offensive, necessitating a thorough cleansing. This 

 was given, together with a reduction in the amount 

 of plant-life, and the first change of water for over 

 two years. The pruning of the weeds proved to be 

 a somewhat dangerous experiment, plant growth at 

 this season of the year naturally almost ceasing ; this, 

 together with the exceedingly severe winter, for a 

 short time imperilled the maintenance of the whole. 

 Fortunately all, however, has gone well, and meli- 

 certa has continued abundant ; so numerous, indeed, 

 as to become so crowded upon the somewhat scanty 

 plants as to cause them to attach their tubes to one 

 another in the manner we are informed more common 

 in the American waters than our own. I have to 

 add that I still consider the plants named in my 

 previous communication to be very good plants for a 

 small aquarium. The sticklebat still survives. Can 

 any reader inform me as to the natural duration of 

 life of this fish 1—J. W. Measures, M.R.C.S. 



ZOOLOGY. 



Mounting Shells. — From a paragraph in the 

 April number of SciENCE-Gossir, I see that a 

 correspondent has got into difftculties on the above 

 subject. To my mind mounting good shells on tablets 

 is downright sinful, as, no matter what mounting 

 media are used, the specimens are certain to be more 

 or less injured. Though I do not " mount " my own 

 collection, I can speak with considerable experience 

 as to its pernicious effect, as only too many of the 

 specimens I receive in exchange are spoilt by one or 



more unsightly patches showing where they have 

 formerly been fixed to tablets. Judging from the 

 instances I have seen, the various gelatine cements, 

 especially those which are applied in a heated con- 

 dition, are the worst offenders. At the Natural 

 History Museum I believe they are very thick gum 

 arable, which is open to less objection, but perhaps 

 the best cement, though possibly not a very secure 

 one, would be wax (preferably such as is used for 

 modelhng) as it can be readily softened by moulding 

 in the fingers. But why mount shells at all ? a 

 collection is far more useful when it is possible to 

 take up each specimen separately and examine it on 

 all sides without the necessity of first detaching it 

 from a mount. Undoubtedly the best, though un- 

 fortunately rather expensive, method of storing shells 

 is to keep them in glass-top boxes, rectangular being 

 superior to circular ones. The most convenient 

 dimensions aie : depth three inches ; width two and 

 four inches ; .length, varying in half inch steps, from 

 one inch upwards. The British Mollusca and part of 

 the general collection at the Natur^i History Museum 

 are arranged in this way. Card-board trays come 

 next in order of merit, and as they can be easily and 

 quickly made by an amateur after very little practice, 

 are very cheap. The superficial dimensions given 

 above for boxes will be found convenient for these 

 also, but a depth of half an inch is sutticient. In 

 order to save work, the corners need not be bound. 

 In my own collection through want of funds, boxes 

 and trays are used together in the same drawer, the 

 boxes being reser\'ed for delicate specimens which 

 might be broken if loose in a tray. As the boxes and 

 trays are made on the same system they fit in exactly. 

 While on this subject, I might refer to another method 

 of spoiling shells, namely writing on the specimens 

 themselves. Names and other information should 

 always be written on a slip of paper placed in the box 

 or tray, but I hope soon to speak about labels more 

 at length.— .5". Pace, 252 Fulham Road, S.W. 



A NEW VARIETY OF Helix Cantiana.— The 

 specimen to which the following description applies 

 was taken from near Sittingbourne, in Kent, by Miss 

 Muriel Norton, and forwarded to me for the purpose 

 of naming by "six. W. E. Swanton, who has it now in 

 his collection. As far as I am aware, the variety is 

 new — indeed, very few varieties of H. cantiana have 

 been described — but, as its deviations from the type 

 are distinctly marked, I have considered it worthy of 

 a variety-name, and have called it var. caiialiciilata. 

 The specimen resembles in some features what I have 

 previously described as var. elevaia in the first 

 number of the " Conchologist " (readers of this note of 

 mine on this variety will kindly oblige the writer by 

 erasing the semicolon between the words "spire" 

 and " compressed," and in reading "canaliculate" 

 instead or " canaliculata,") but, in this instance, the 

 spire is depressed and does not rise about half a 



