ZOOLOGY. 355 



centration of the liquids of the plant by the suction of grubs. This 

 concentration, by augmenting the vitality of the part, determines, at 

 the same time, the hypertrophical increase. M. Duthiers thinks a 

 third division may be made for the galls which present the characters 

 of both external and internal productions. These may be called 

 mixed galls. The galls in artichokes are in this category ; they are 

 caused by the hypertrophy of a bud, in whose centre a small external 

 gall is developed. 



NESTS OF HUMMING BIRDS. 



At a recent meeting of the London Zoological Society, Mr. Gould, 

 the eminent naturalist, exhibited a collection of the nests of Humming 

 Birds, exemplifying the habitual characteristic structure of several 

 genera. The first group to which his remarks were directed were the 

 Hermit Birds, (Phaethornis,') who invariably build at the extremity of 

 leaves, perhaps from the protection which that situation affords against 

 'the attack of monkeys and other predatory animals. Oreotrocliilus 

 builds a beautiful nest attached to the side of a rock. Heliomaster 

 mesoleucus makes a nest in a beautiful species of moss of the genus 

 US-no., depending from the trees of the Brazilian forest. Most of the 

 nests are cup-shaped, some in forks, some in branches, some on leaves, 

 some in ferns, shallow and delicately formed, ornamented in the most 

 various manner with feathers, or with festoons of moss and of lichen, 

 especially in the genus Htjlocharis. The differences in the eggs of 

 Humming Birds are not very observable, being invariably two in 

 number, white and oblong, with one supposed exception namely, a 

 species inhabiting the Upper Amazon, which, according to Mr. 

 Edwards, lays a spotted egg. But the difference of structure of the 

 nests sufficiently corroborate the generic divisions into which these 

 birds have been separated by modern ornithologists. The attachment 

 of the lichen and other ornaments is effected by the use of fine cob- 

 webs. The humming birds generally place their nests in open situa- 

 tions, regardless of the intrusion of man, to which, however, the 

 remote localities occupied by many of the species but little expose 

 them. They have a little sharp note, which, although similar, has 

 sufficient variety to enable the collectors to decide that they are within 

 the range of a new species before they have seen it. 



THE GREAT AMERICAN ANT-EATER. 



Among the few animals that have hitherto resisted most attempts to 

 bring them alive to Europe, is the Great American Ant-eater (Myr- 

 mecopJiaga jubata). The difficulty of procuring for it proper food 

 seems to have been one cause of this failure. The late Earl of Derby 

 on two occasions received living specimens of the curious animal in 

 question, but each soon died. We have now to record the fact, that 

 one of these singular creatures has at last been secured alive by the 

 Zoological Society, and is at present hi a prosperous condition in 



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