272 FIELD SKETCHES. 



come forth. He perhaps finds that the earth in the first pot devclopes 

 the insect sooner than the earth in the other two ; that the earth in the 

 second takes three or four more clays more than the former, and lastly, 

 that the third requires several days more than the latter to effect the 

 required transformation. With such insect embryos as are naturally 

 deposited in damp soils, the results of the experiment would be the 

 contrary. But, whatever results he might obtain, they could not fail to 

 furnish him with more accurate data from which he might expect at 

 certain periods the appearance of an insect. Having investigated in the 

 above manner the causes of the irregularities of insect development, 

 the entomologist will now pursue his researches with greater success, 

 and build his- expectations upon better foundations ; but still other 

 causes will exist which it is not so easy to take into calculation, and to 

 make allowances accordingly. There will be rain, drought, sunshine, 

 &c., the degree of influence exercised by either of which upon the 

 embryos we cannot accurately determine, unless it be by examining by 

 dissection or otherwise, how the transformation of an embryo belonging 

 to any species is progressing to its perfect state in thsoe fields in which 

 the naturalist is in the constant habit of pursuing his researches. 

 London, March, 1833. 



FIELD SKETCHES. 



BY RURICOLA. 



IN my grounds this month, within a few yards of each other, have 

 been two yellow buntings' nests : yellow yowleys, as they are commonly 

 called in this country, where the English vernacular name of yellow- 

 hammer is little known. One of these nests was built on the ground, 

 on a slight slope, in the midst of a tussock of dry withered grass, shel- 

 tered by the branch of a young spruce fir and by a low furze bush. 

 The other was situated in a white-thorn hedge, at about 18 inches 

 from the ground. Some withered grass rose about this nest also ; but 

 the situation of it is unquestionably in the hedge, where it rests in a 

 fork formed by the stem and one of the branches, at the height already 

 mentioned above the ground. I trouble you with this statement, as 

 affording within a short space examples of the two situations for build- 

 ing chosen by this bird, as noticed in the second edition of Colonel 

 Montagu's Ornithological Dictionary. Colonel Montagu says, that " the 



