May 1, 1S67. 



HABDWICKE'S SCIENCE-GOSSIP. 



119 



Spawning of Frogs. — Frogs began to spawn 

 here during the warm weather which we had at the 

 end of February. I did not note down the exact 

 date, but on March 2nd I passed a quantity of 

 spawn imbedded in ice. Would the vitality of this 

 be destroyed ? A strange notion prevails here that 

 three-year-old frogs destroy all the four-year-old 

 frogs. The females are generally larger than the 

 males, and hence the idea that they are of different 

 ages ; whilst the fact that many of the females do 

 die after spawning, — from exhaustion, or because 

 from weakness they cannot escape from their 

 enemies, the boys, — has given rise to the belief that 

 the smaller ones kill the larger ones. Frogs arc 

 also looked upon as good weather-guides. If they 

 are of a bright yellowish colour, it will be fine 

 weather; if of a dull brown, it will rain. Frogs 

 certainly vary greatly in colour, but whether they 

 are capable of changing their hue, like a chameleon, 

 I do not know. — Robert Holland. 



Hyalodiscus. — Your correspondent " R. G." 

 kindly sent me a slide of diatoms from under Menai 

 Bridge^ containing one specimen of what he considers 

 to be Hyalodiscus subtilis, var. hrvis. I find abundant 

 specimens of the same form in slides of diatoms 

 from Teignmouth and Isle of Arran. I believe it to 

 be a Podosira, possibly Podosira maculata (S.), see 

 Pritchard, p. 815, 4th edition, and S. B. D., vol. ii., 

 p. 51, pi. 19, fig. 328. The disc is certainly convex, 

 and not flat, convexity being the distinguishing 

 characteristic of Podosira as opposed to Hyalodiscus. 

 The markings, moreover, are not like an engine- 

 turned back of a watch, but the disc appears ob- 

 scurely divided into compartments, each with two 

 sets of oblique, intersecting, distinct strise. — H. R. 



The Lackey Moth. — I recently found some 

 eggs, greeuish and of a conical shape. From a 

 drawing 1 have seen, I believe them to be the eggs 

 of the Lackey Moth. If so, a rather curious cir- 

 cumstance presents itself. In all books on insects 

 that I have read, the eggs of the Lackey Moth are 

 represented as being made in a ring round the 

 branch of a tree. Now these eggs were laid on 

 the trunk of a tree, and in a patch not — a ring. Is 

 this a common occurrence ? I have never seen it 

 noted by any writer on entomology. Perhaps some 

 of the readers of Science-Gossip may have met 

 with a similar instance. — H. H. O'Farrell. 



Brimstone Butterfly. — I saw here this year 

 the first Brimstone Butterfly on the lothof February. 

 I believe this butterfly has no regular time for its 

 apparitions, as several others; I have observed since 

 nearly twenty years the periodical visits of birds, 

 insects, &c, and have seen it sometimes very soon, 

 when there was only a glimpse of fine weather. In 

 1852 it appeared on the 21st December ; in 1862 on 

 the 11th of January. The Brimstone Butterfly is 

 called in French " Citron," the Brimstone Moth 

 "Soufre."— B. Melle. 



Mice and Cockroaches. — In the struggle for 

 existence, is there any antagonism between mice 

 and cockroaches ? My house at one time, and for 

 years, was swarmed with the latter, of which I have 

 a special horror. At that period we had no mice. 

 Within the last year or two mice have taken their 

 abode with us, and are now not only numerous but 

 supreme, the cockroach having disappeared before 

 it, and this without any poison or other means 

 having been resorted to. Have the mice eaten 

 them or frightened them away ?— /. B. Keene. 



Sensitive Plants (v. S. G., p. 91).— I have seen 

 in some authors that the false Acacia (Robinia 

 pseudo Acacia), w;hen suddenly and violently shaken, 

 seems also sensitive, but I never experienced that. 

 — B. Melle. 



Babeer (v.S. G. p.90).— Might that cane not bethe 

 Briophorum Cannabhium, called, 1 believe, in India 

 " Bhabhar," and employed there with other grasses 

 for making ropes ? — B. Melle. 



An Egg within an Egg (v. S. G. p. 91). — We have 

 here, in the Museum, an egg enclosed in another, 

 just as the one described by C. A. J. A communi- 

 cation was made last year to the Academie des 

 Sciences of a similar occurrence. The case seems 

 to happen occasionally. — B. Melle. 



Santonine, &c. — E. M. will readily procure 

 most_ beautiful crystals of santonine from its solu- 

 tion in chloroform. By varying the strength of the 

 solution, and the quantity laid upon the slide, E. M. 

 will procure a variety of combinations. Let the 

 solution evaporate spontaneously. My specimens 

 are mounted dry. Has your correspondent tried 

 Naphthaline ? If not, he should do so, thus. Place 

 a flake or two at the bottom of a watch-glass, over 

 which put a lidless salve or pill box, with the 

 bottom uppermost, and with a hole punched in it ; 

 over the hole place your glass slip, and apply a 

 spirit-glass to the under side of the watch-glass, 

 when the vapour of the naphthaline will condense on 

 the slide in most exquisite crystals (vide Intell. Obs. 

 vol. vi., p. 111). I have not yet been very suc- 

 cessful in mounting this highly volatile substance. — 

 J. E. Whalley. 



Double Pear. — A notice of a peculiar pear 

 in Science-Gossip reminds me of one I saw some 

 time ago. It differed from that described by your 

 correspondent in being a double pear, the second 

 growing out of the eye of the first— hanging and 

 separated from it by a stalk. This pear grew on a 

 tree against a wall. — H. Smith. 



Stickleback out of Water.— The other day 

 the boys were turning out the aquarium, and left 

 the fish — which were three-spined sticklebacks 

 (Gasterosteus aculeatus) — rather too long in a 

 bottle. The consequences were that many of them 

 died. The aquarium glass was refilled, and the 

 boys put the live sticklebacks in, leaving the sup- 

 posed dead ones— of which I rescued three — in 

 a saucer, without any water. This was at 1 p.m. 

 Just before I went to bed — it being then 10 p.m. — 

 I saw that the boys had not taken away the sup- 

 posed dead fish. I determined to give them a small 

 lecture for the omission ; aud poured a little water 

 into^the saucer, and put it on one side. The next 

 morning, when I told a boy to take it away, he 

 said, " Why, sir, here is one of the fish alive ! " 

 And sure enough there was. We put it into the 

 aquarium, and it has lived a week. Do sticklebacks 

 generally live six hours without water ? — P. R. R. 



Santonine. — To prepare slides of rosette crystals, 

 place about ten grains of santonine in a small test 

 tube, and pour upon it one dram of chloroform, 

 and dissolve by a gentle heat ; then drop upon 

 glass slips a small portion of the solution, which 

 will rapidly evaporate, depositing fine rosette 

 crystals of the salt. Canada balsam or Deane's 

 gelatine medium will answer well for mounting 

 them. — P. R. Martin, Redland, Bristol. 



