12 



HARDWICKE'S SCIENCE- GOSSIP. 



might, to make her supposed enemies believe her 

 painfully-acted and harshly-uttered lie. 



A word with reference to her nest. This species 

 of Wren usually builds a very commodious and neat 

 nest, and in a concealed spot; not, as in this instance, 

 on the top of a window-frame, in full view, like a pee- 

 wee's nest. It was, really, an instance of what is 

 constantly to be seen in nest-building, — carelessness 

 and laziness on the part of some individuals of 

 every species. In my studies of thousands of birds' 

 nests, 1 have found it to be true that an exposed 

 position will be chosen occasionally, because the 

 twigs and branches so grow as to lessen the labour 

 of building the nest. Birds are " smart " in many 

 ways, but have their weaknesses, too ; which fact, I 

 think, is one of the strongest arguments in favour 

 of the theory (?) that their mental powers are iden- 

 tical with those of mankind, differing only in degree. 

 In consequence of our early education, this becomes 

 difficult to believe ; but, indeed, could we obliterate 

 from our minds all knowledge of even the word 

 " Instinct," when we enter the haunts of birds, a 

 fuller and far more correct knowledge of them could 

 be obtained in one summer than has been gathered 

 since the days of Linnaeus. 



Considerable comment having been made with 

 reference to my note on the eggs of the Yellow-bird 

 (Chrysomitris tristis), in the Gth vol. of this maga- 

 zine, wherein I stated that about thirty per 

 cent, of the eggs had yellowish-brown and some- 

 times purple marks, I determined to take copious 

 notes of the colouring of the eggs of all our breeding 

 birds during the spring and summer of the last 

 year ; and I will conclude this article with a brief 

 resume of my observations, and the conclusions I 

 derived from them. 



In making a classification of my notes on the eggs 

 observed, I found, first, that birds laying white eggs 

 in small numbers, as the Yellow-bird and Pee- wee 

 {Sayornis fuscus), vary a good deal, in that occasion- 

 ally a single egg, or oftener the full complement, 

 will have some dark markings about them ; while, 

 on the other hand, birds that ordinarily lay marked 

 eggs occasionally lay one, or a whole " sitting," 

 pearly white ; as the Grass-finch (Poocostes gra- 

 minetts) and the Song-sparrow (]\felospiza melodia). 



Secondly, that birds like the Quail (Ortyx vir- 

 ginianus) and the Woodpecker, laying large numbers 

 of white eggs, do not vary at all. 



Thirdly, that birds laying a small number of 

 dark-coloured eggs, as the Cat-bird, Robin, and 

 Wood-thrush {Tardus mustelinus), frequently lay 

 a whole series of much lighter hue than usual, 

 but never any exhibiting well-defined marks upon 

 them. 



Fourthly, that supernumerary eggs, with white 

 shells, are not unfrequcntly deposited ; and these I 

 believe are, as a class, infertile. I have found them 

 in the nests of our chipping Sparrow, the Lob-o'-link 



{Dolichonyx oryzivora), Blue-bird, and Great-crested 

 Ely catcher (Myiarckus crinitus). 



I believe, therefore, that the colour and markings 

 of eggs are so far variable that no nest can posi- 

 tively be identified by the eggs alone, and not 

 always if both the construction of the nest and the 

 markings on the eggs are considered. We all know 

 how " geographical races " of a species vary as to 

 both size and colour, and this is equally true of the 

 nests and eggs. 



NOTES ON QUILL-WORTS {Isoetes). 



1NCE the date of my notice of the Isoetes 

 Hystrix, Duriai, and the Guernsey plant, in 

 Science-Gossip of November last, p. 25S, my atten- 

 tion has been drawn to the Flora of France and Cor- 



s 



Fig. ". Isoetes Hystrix. 



sica (1855) of Grer.ier and Godron, containing full 

 descriptions of all the Isoetes found within those 

 limits, including the /. Duricei, Bory, and the I. 

 Hystrix, Bory, Durieu, and Cosson, which quite 

 confirms my statement that the Guernsey plant is 

 not the /. Hystrix, Bory. 



