274 



HARDWICKE'S SCIENCE-GOSSIP. 



NOTES ON THE COMMON FROG IN A 

 STATE OF DOMESTICATION. 



[Continued from /. 248.] 



THE abnormal condition of the frog's skin, etc., 

 mentioned above, on the 26th July and the 16th 

 August, I believe to be the beginning of a disease by 

 which a great number of frogs often die, while the 

 white matter on the glass of its house (on 26th) may 

 have been the early stage of a fungus often very fatal 

 to frogs. In April, 1881, I came across a marked 

 instance of death among frogs with a disease similar 

 to what manifested itself to this specimen in the 

 abnormal state of its skin, etc. I found a number of 

 frogs by the side of a dry sandy road, nearly one- 

 half of which were dead, and the others in a dying 

 state. Their skins had a similar appearance to that 

 described in this specimen. Several of the dead and 

 dying that were dissected had the skin of their 

 bodies extended like a blown bladder, and it was 

 remarkably hard. How so many frogs met with this 

 disease may be accounted for as follows : — About 

 250 to 300 yards from where the frogs were, there 

 was a loch, in which were a great many frogs, and 

 those found dead and dying may have left the loch in 

 search of food on the grass, in the dewy night or 

 morning, but when the warm April sun arose the 

 short grass became dry, and being unable to find 

 shelter (in the bright day of sunshine that it was), 

 and as the want of water had stopped the action of 

 their skin — the result was death. 



During the night between the 24th and 25th 

 August, the frog began to croak, and on the morning 

 of 25th I was beside it when croaking ; the bag or 

 membrane below its chin was much extended. 

 When in bed on the night between the 26th and 

 27th August, I again heard the frog croaking, and 

 also between 7 and 8 p.m. on the 29th, it croaked 

 when there was no small noise with the children. 



Observations on this frog confirms the statement, 

 "that frogs only take living insects." In no 

 instance did I observe this frog take any creature 

 but was moving in some way or other, and it often 

 sat and watched with great patience until the insect 

 began to move when this suddenly disappeared in its 

 mouth. I tried the frog to take dead insects by 

 attaching something to make them move, but never 

 succeeded ; it once, however, mistook the shadow of 

 a house-fly so moved, at which it sent its tongue, but 

 being once deceived I never got it to do so again. 

 This, I would say, was a lesson from experience ; 

 but experience sometimes taught it wrong, as the 

 following instance will show. A medical gentleman, 

 on a visit from Ireland, was anxious to see the frog 

 taking insects, but although house-fiies were put in 

 beside it, it took no notice of them, for the reason, I 

 believe, that during that day many flies had alighted 

 on the outside of its glass house, some of which it 

 had tried to capture, but in vain ! What it may 



have learned regarding leeches, I never again put it 

 to trial; but on the 15th August, I gave it a large 

 black snail (Arion) at which it made several at- 

 tempts, but was unable to lift it with its tongue. It 

 is possible that the horse-leech may be a real enemy 

 to the frog. A writer in "Nature" of 1st July, 

 1S86, page 194, in writing on the enemies of the 

 frog, mentions that "at Lake Elphinstone (100 

 miles from Mackay), I once saw a small frog (//. 

 rubella) in a house in a very excited condition. 

 On examination, I found a large leech on its tongue. 

 This specimen, with the leech, I gave to Mr. 

 Boulenger of the British Museum, where it may be 

 seen." I observed that this frog changed its colour 

 in no small degree, as it was affected by fear or 

 otherwise. It also had the power, to a limited 

 extent of protruding its eyes from their sockets, and 

 the back of the eye-balls seemed to be used in 

 connection with swallowing ; they were often sunken 

 downwards and backwards into its head till they 

 were hidden, i.e. when in the act of swallowing. 

 The movement of the frog's tongue in taking in. 

 an insect is so sudden that I could never follow it 

 with my eye, although close beside the creature. 

 In the "Zoologist" for 1S45, vol. iii., p. 826, 

 R. Q. Couch, Esq., M.R.C.S.L., writes :— " The 

 rapidity with which this is effected" (i.e. taking ot 

 insects with the tongue) "is so great, that it is not 

 at all times easy to notice it, unless within a foot or 

 two of it at the time." 



To the farmer and gardener, I would say, the frog 

 is their friend, in the destroying of insects and 

 snails ; and it should be protected from foolish cruelty 

 and wicked destruction, so often waged against the 

 harmless creature. To those who are contented to> 

 study nature, the frog, as one of God's creatures, is 

 well worthy of study and makes an interesting pet. 

 The cause of this frog's death, as already stated, was 

 its eating a large earwig, which, as the dissection 

 showed, had pierced its gullet. This happened on 

 the 22nd September, and on the afternoon of the 

 23rd, the frog began to cry in a very strange manner, 

 and, on its house being opened, it sprang out, and 

 then got into a greatly convulsed state ; it was put in 

 a little cold water, but lay greatly convulsed for over 

 two hours, but again at night it was as lively as if 

 nothing had happened, and also the day following, 

 and when I last saw it at 9 a.m. on the 26th, but 

 at I P.M. it was found dead. The dissection showed 

 that inflammation had set in around the perforations 

 in its gullet. In its stomach were pieces of the 

 earwig, some house-flies, and some earthy matter out 

 of earth-worms that it had eaten. 



Taylor, 

 Sub-curator, Free Museum, Paisley, N.B. 



Messrs. Dulau and Co., 37 Soho Square, have 

 just issued a useful catalogue of works on astronomy, 

 magnetism, and meteorology. 



