HARDWICKE'S SCIENCE-GOSSIP. 



11 



seems clear tljat the power to do so must have been 

 first acquired, and the addition to it, in being able 

 to repeat the sound so as to make it seem as though 

 uttered where the mimicked note is heard, consti- 

 tutes the power in question. Such an addition to 

 the power of mimicking other birds, and the cries 

 of small mammals, would at once prove advan- 

 tageous in misleading a pursuing enemy, as a small 

 bawk ; and the Chat would not be slow to learn 

 this, and profit by the knowledge by constaut re- 

 petition and practice. A bird readily appreciates 

 the benefit it derives from any unusual circumstance 

 or series of them, and will remember long, and 

 endeavour to secure their repetition, so far as it was 

 instrumental in bringing it about. In this way 

 a new habit readily becomes characteristic of a 

 species, first locally, and then throughout the entire 

 range of its habitat. 



About the middle of June the young birds had 

 left the nest, but continued with the parent birds, 

 and were fed by them. From this time until 

 August 5th, when both old and young left the 

 neighbourhood, I failed to detect any attempt even 

 at singing on the part of the young ; and the more 

 marked features of the song of the parent birds 

 were but seldom heard after the young had obtained 

 a sufficient flight-power to insure their safety. Both 

 the mimicry and the ventriloquism seem to be 

 wholly exercised by the male in securing safety to 

 the young and the female while sitting, if we except 

 his occasional exhibitions on his arrival in spring, 

 which are tests of his power, for his own satisfac- 

 tion at first, and when the females arrive, proofs of 

 it to theirs. 



On the 15th of July a pair of Bewick's wrens 

 Thryothonis Bewickii) appeared in and about one of 

 my outbuildings, and in a day or two, having fixed 

 upon a suitable spot for their nest, commenced 

 carrying the materials necessary for its construction. 

 As they were not at all timid, I had abundant op- 

 portunities of watching them while so employed, 

 and I must admit that their modus operandi was 

 very damaging to the poetry of birds' nests. After 

 the first few strands of long, tape-like grass had 

 been arranged upon the beam, the birds came toge- 

 ther to the spot, each carrying a blade of grass or 

 other equally flexible material. The female then 

 sat in the unfinished nest, while her mate wound 

 loosely about her the materials they had brought. 

 This was repeated until the foundation of the nest, 

 about an inch deep, was completed, when the female 

 ceased carrying materials, but waited for her mate's 

 return with such soft materials as he could find for 

 the lining of the nest. This was simply placed upon 

 the nest loosely, and not at all adjusted. When a 

 considerable quantity had been piled up, the female 

 " burrowed " into it, and turning round and round, 

 succeeded in treading down a comparatively smooth 

 depression in the floor of the nest, and the larger 



1 strands were rudely arched over her, but did not 

 really form a roof. In three days the nest was 

 completed, and was nothing better than any child 

 could have made with the same materials by 

 wrapping, winding, and slapping it over his fist. 

 Not one particle of ingenuity was displayed at any 

 time. On the fourth day the first egg was laid, and 

 on this day a cat succeeded in catching the male 

 bird. As the female did not seem to miss him very 

 much, and it was this mishap which made the sub- 

 sequent study of the nest and the female bird pos- 

 sible, I thanked the cat for the interference. The 

 widowed wren wandered about quite as usual, con- 

 stantly uttering a very cheery chirp, and gathering 

 up a goodly quantity of insects every day. One 

 egg was laid each day, until four had been depo- 

 sited, when she commenced sitting. The fourth 

 egg was pure white ; the others of the usual hue 

 and markings. An interesting physiological feature 

 of the case might be profitably discussed, but will 

 here be but briefly referred to. This species of 

 Wren usually lays from seven to nine eggs, and 

 hatches them all. Did the influence of the male 

 only reach to the third, or possibly the fourth egg ? 

 Of the four eggs laid, the last one did not hatch, 

 and I judged from its contents that the yolk had 

 been imperfect. Again, did the death of the male 

 bird indirectly cause the shell of the fourth egg 

 laid to be wholly colourless ? The season was too 

 advanced to make any experiments during the 

 remainder of the summer. 



After the young were a day old, the parent bird 

 was seldom seen except for a moment at a time, 

 when it would dart into the workshop through a 

 knot-hole, carrying a beetle larva or caterpillar, and 

 giving it to them, off she would go again, usually to 

 the roof of another building, and there chirp and 

 fairly scream, fluttering about in a distressed manner, 

 as though determined to make the passers-by believe 

 she had a nest anywhere except in the spot really 

 occupied. This habit was so marked in all its fea- 

 tures as to attract the attention of the whole family ; 

 and when the workshop, which was continually 

 visited for a few moments at a time during the day, 

 was occupied on her arrival with food for her young, 

 she would dart out as rapidly as she came, and go 

 through her accustomed antics on a distant roof, 

 the while retaining the food for her young in her bill. 

 By the 12th of August the young had left the nest, 

 and in a day or two they left the neighbourhood. 



The song of the male Wren is, I think, very fine, 

 and far more melodious than that of Troglodytes 

 cedon, the common house-wren of our country. But 

 there is not in it, or in the utterances of the female, 

 any trace either of mimicry or ventriloquism, and I 

 could not but recall the advantage the Chat had in 

 remaining comfortably at home and sending his 

 voice on an errand, when I saw the anxious Wren 

 labour with both voice and body, and with all her 



