The Zoologist— April, 1868. 1159 



and first stages of pregnancy, may under certain circumstances have 

 a considerable influence on the formation of the embryo. So it would 

 not be of itself improbable that Nature would follow out in this 

 manner her design once advanced. 



Nevertheless, several facts speak against this explanation. I„ the 

 first place, experience which proves that the eggs of the cuckoo are 

 differently coloured and marked, according to the localities, or (as 

 Temminck says) « they depend upon the locality." * This fact, even 

 under the limitation pointed out in the note, would not be enough to 

 explain if one would set out from the view put forth in the text, since 



* It is evident that this assertion of Teraminek's must be modifier) i„ that it 

 strictly appertams to certain, but by no means to all, localities; that is , J 

 spots where certain cuckoos' foster-parents live near one 'another I 

 abundance, while there are not many other warblers in the neighbourhood, the 

 cue oo s egg. w, 1 assume entirely the type of the eggs of the predominating c 



far the n rT ,' T '? "^ ^^ "^ Calamoherpe aruudi aJea, by 

 fa. the most abundant breeder among the warblers, is wont to dwell : and in fact his 

 assumpuon w.ll be confirmed in a surprising manner by the knowledge, « ! 

 e penence, that almost all the cuckoo's eggs from the Badetzer pond near Ze bT 

 where the cue oo is very abundant and the reed warbler [" teichroLa ,ge ' ] | Is the 

 most common bud, assume the type of the last-named bird's eggs. Moreover „ h e 



Motadla alba finds ,ts favourite haunts; in marshy meadows and moors whee 

 Authus pratens.s breeds in the greatest abundance (as m all probability in he net 

 bourhood of Leyden,and in the immediate environs of Herr von Homeyer who in h s 



el z uc :r °i ihe Bmis of pomei;,nia; p - io ' ai, ^ es ^ *° s«S 



eggs principally ,n the nes.s of the [« weissen bachstelge "] pied wagtail and the 

 wmsenp.eper-] meadow pipit); , astly , h districls where eIcL mi iia Spa . 



to 7 f Z T ° lS " aP,mreUt ' y thC CaSC iU lhe -ighbourhood o Lo • 

 h oughout all these places will the cuckoo's eggs assume various predomin ^ 

 c lours, accordtng to the various localities. In opposition to this view JTeZ^ 



the cuckoos eggs depends upon age, state of health, vigour in laying ('abondance de 



la pom. ), and the kind of food." Of all the explanations of Jfact bV " Zon 



which has the least to say for itself, so much influence one is inclined to Low to Z 



arguments above mentioned for the origin of other varieties of eggs. Dr. GW 



Handb.d N.G. der V6g.l Europa's, i. p. 448) supposes that generally, but cer 



tainly not tnvanably, nearly all the cuckoo's eggs laid in the course of one v nd 



by vanous hens, at least such as happen to be laid at the same time, are very similar 



o o„e another ; and then adds, thereupon, this appearance may be readily e,pi i ed by 



he general use of tins or that sort of food in the course of one or another y'ear, sincl 



«. mo st summers just ibis or that sort of caterpillar appears in a neighbourhood in 



peculiar abundance, and for some lime generally presents itself to the hen cuckoos in 



that place in great numbers. 



