220 



nf Natural 3$&t0rg J 



countless myriads of their petrified remains 

 which fill so many limestone-beds of the 

 transition formations, and compose vast 

 strata of entrochal marble, extending over 

 large tracts of country in Northern Europe 

 and North America. The substance of this 

 marble is often almost as entirely made up 

 of the petrified bones of Encrinites as a corn- 

 rick is composed of straws. Man applies it 

 to construct Ms palace and adorn his sepul- 

 : chre ; but there are few who know, and fewer 

 ' still who duly appreciate, the surprising fact, 

 that much of this marble is composed of the 

 skeletons of millions of organized beings, 

 once endowed with life, and susceptible of 

 enjoyment, which, after performing the part 

 that was for a while assigned to them in 

 1 living nature, have contributed their remains 



I.ILT ENCKINIT..-OW.ORINOB WMIFORMIS.) 

 towards the composition of the mountain 

 masses of the earth. Of more than thirty 

 species of Crinoi'deans that prevailed to such 

 enormous extent in the transition period, 

 nearly all became extinct before the depo- 

 sition of the lias, and only one presents the 

 angular column of the Pentacrinite : with 

 this one exception, pentangular columns first 

 began to abound among the Crinoi'deans at 

 the commencement of the lias, and have 

 from thence extended onwards into our 

 present seas. Their several species and even 

 genera are also limited in their extent : e. g. 

 the great Lily Encrinite (E. moniliformis) is 

 peculiar to the muschel-kalk, and the Pear 

 Encrinite to the middle region of the oolitic 

 formation. 



ENIIYDKA. The generic name of the 

 Sea Otter of California (.Mustcla lutris, Lin.) 

 See OTTER.] 



ENTOMOPHAGA. The name given to 

 a group of Hymenopterous insects, whose 

 larva; generally feed, parasitically, upon 

 living insects. 



ENTOMOSTRACA. A division of the 

 class Crustacea, comprising those animals 

 which have only a slight integument in the 

 form of a shell to protect them ; of which 

 the genus Cyprus (many species of which oc- 

 cur in this country) may be given as an ex- 

 ample. Their exceeding minuteness and 

 extreme delicacy of structure have deterred 

 most naturalists from examining them and 

 studying them as they require to be studied 

 fresh from their native habitats. The 

 difficulty of preserving them obliges the na- 

 turalist to seek them in their secret lurking 

 places the fresh-water ponds and ditches, 



and the little pools in the rocks on the sea- 

 shore, where they are chiefly to be found, 

 and to study them as it were on the spot, 

 with the aid of his microscope. Dr. W. 

 Baird, who has some ingenious remarks on 

 Entomostraca in " The Zoologist " (after 

 alluding to what Latreille had said respecting 

 their organs of mastication being too minute 

 for human observation), says, " The organs 

 of mastication are not however the only or- 

 gans that are worthy of being noticed. The 

 beautiful and delicate structure of their feet 

 and branchial appendages are worthy of all 

 admiration. These latter organs are almost 

 constantly in motion, and present a most 

 interesting appearance when viewed under 

 the microscope. The extraordinary method 

 they have of reproducing their young, with 

 the transformations which some of them un- 

 dergo in an early stage, are subjects which 

 might occupy a considerable time in de- 

 scribing, and which cannot be attended to 

 without exciting the greatest interest in the 

 mind of the observer." Dr. Baird has mo- j 

 nographed all the British species, and pub- j 

 lished also descriptions of several exotic 

 species. [See CYPKIS.] 



ENTOMYZA. A genus of birds belong- 

 ing to the Meliphagidce, of which we may 

 mention one of the best known species. 



ENTOMYZA CYANOTIS, called by the . 

 colonists of New South Wales BuiE-EvK. 

 This bird is found almost exclusively on the 

 Eucalypti, searching among the blossoms | 

 and smaller leafy branches for its food, j 

 which consists partly of insects and partly i 

 of honey, and, as others of the group do, ! 

 probably, on berries and fruit. They are ' 

 bold and spirited birds, pugnaciously chasing ; 

 and drawing about the other species resorting j 

 to the same tree. Its cry is loud and mono- ' 

 tonous. In every instance that Mr. Gould 

 found its eggs, they were deposited on the 

 deserted, dome-shaped, large nest of the I'o- 

 matarhiuus, never within the dome, but in a 

 neat round depression on the top. It com- 

 mences breeding early, and has at least two 

 broods in a year. 



ENTOZOA. A name given to an exten- 

 sive series of low-organized invertebrate 

 animals (generally vermiform), the greater 

 part of which are inhabitants, during their 

 whole period of existence, of other animals, 

 whose internal organs they prey upon. They 

 have colourless blood, no respiratory organs, 

 and no articulated members for locomotion. 

 Many of them infest the human body. [See 

 INTKSTINALIA.] 



ENTOZOON. A name given to a curious 

 parasite, found by Simon in the sebaceous 

 follicles of the skin : Mr. Erasmus Wilson 

 has given an elaborate description of it, with 

 figures, in the Philosophical Transactions. 

 Mr. Owen has applied the name Dcmodex 

 to it, the word Entozoon being pre -occupied. 

 It is believed to belong to the Rot if era, but 

 there is still some doubt of its position. 



EPHEMERA:EPHEMERID^E. A genus 

 and familyof Neuropterous insects,which take 

 their name from the short duration of their 



