490 Retrospective Criticism. 



hatch (see the preceding article) is also in its habits, though not in name, 

 a tree creeper, and, as sho^fn above, does in winter associate with the 

 titmice, these coincidences almost incline one to suspect that the creeper of 

 Lancashire must be the nuthatch ofpther counties. — J. D. 



Cries of Frogs. — Mr. Blair (Vol. IV. p. 280.) mentions the cries of frogs 

 when pursued by snakes in America. I have heard them from our common 

 frog (/?ana temporaria), under similar circumstances ; but possibly the fact 

 may be better known than I am aware of. — J. S. Henslow. Cambridge , 

 Aug. 4>. 1831. 



To the residents in the fens of Cambridgeshire, where frogs and snakes 

 abound, the cries of frogs are very familiar. Half-grown cats, in the excess 

 of their playfulness, occasionally elicit the cries of the frog ; for, on encoun- 

 tering one, they follow after and pat it with the foot, to make it jump for- 

 ward J and when it stops, they will sometimes smell to it, as if curious to 

 know all about it. These processes of enquiry intimidate the frog, and 

 excite its cries. The cries of one once induced me to turn to the spot 

 whence they proceeded, when, -lo ! a rat, about one third grown, had 

 grasped a good-sized frog by the thigh, and was carrying it off. On step- 

 ping towards them, and stamping with my feet, the rat dropped the frog, and 

 retreated into some loose vegetable rubbish lying by, and the frog hopped 

 off; but as I stood still to look at it, the moment all was quiet again, out 

 started the rat, and recaptured his prize, and the cries of the frog were, of 

 course, resumed. I again interfered, and this time drove the rat effectually 

 away. The frog had reason to cry out ; for his death would as surely have 

 followed, as that of those bought in the frog-markets of France. I once saw 

 the mangled remains of a frog in a hole in the base of an old broad wall, 

 and the rat itself alive at the same time in this hole ; the tail of a land newt 

 (Z/acerta vulgaris), and fractured shells of Helix aspersa, also lay at the 

 edge and on the floor of the hole. The wall alluded to is in the old bo- 

 'tanic garden at Bury St. Edmunds ; and this and the other old walls there 

 had, in hard winters, all their cavities near the ground explored, and freed 

 from the snails (^elix aspersa, and probably hispida of Jeffreys in Linn. 

 Trans, also, as a species answering to the characteristics of this abounds 

 there, but is almost too small for the occupation of a rat's time and atten- 

 tion), and the shells more or less perfectly brought to the edge of the holes. 

 It was the land rat which attacked the frog above mentioned ; and this 

 happened late in autumn : the rat in the hole alluded to was also a 

 land rat, and the time at which it was seen there the early part of win- 

 ter : the clearing of snails took place in hard and long frosts, and was pro- 

 bably effected by land rats also. Water and water rats are both near, as 

 the rivers Lark and Linnet pass through the bottom of the garden ; yet I 

 rarely or never saw a water rat on the upper or drier land of the garden, 

 but land rats often. In the hole of a water rat, a large cluster of mangled 

 remains of earthworms was once found, and shown to me by the finder. — 

 J.D. 



Caterpillar of Polyommafus Arghlus feeding on the Holly and Ivy. 

 (Vol. IV. p. 477. note, and Vol. V. p. 205.) — Sir, As I should be sorry 

 to be the means of propagating error, or of putting forth, as /«c^a' in natural 

 history, points which are but of doubtful authority, I beg here to state 

 that when I spoke of the caterpillar of Polyommatus Argiolu^- feeding on 

 the holly and ivy (Vol. IV. p. 477.), I did not mention the circumstance as 

 of my own knowledge, but merely on the authority, cither oral or written, 

 of others, I never saw the caterpillar myself, nor do I know, from expe- 

 rience, on what it feeds ; but I have either been informed by practical 

 entomologists, or have read in some entomologicfil work (or perhaps both), 

 that it does feed on the aforesaid shrubs * ; and I certainly have been the 



* Stephens, in his Illustrations^ says, the caterpillar feeds on the buck- 



