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THURSDAY, JANUARY 20, 1876 



THE ''ENCYCLOPEDIA BRITANNICA" 



Encyclopedia Britannica. Vol.111. (Edinburgh : Adam 

 and Charles Black.) 



First Notice. 



THERE are several important scientific articles in this 

 third volume Avhich we shall briefly notice, the 

 articles generally being quite up to the standard of the 

 preceding volumes. In this first notice we shall refer 

 especially to the articles "Birds" and "Biology." The 

 former article is the joint production of two authors, 

 Professors W. K. Parker and Alfred Newton. 



Prof. Parker has undertaken the anatomical portion of 

 the subject. Allowing himself to be led away in the 

 direction of his favourite line of research, the author has 

 persuaded himself that in the space allotted to him for 

 his article " there is merely room for justice to be done to 

 one category of organs ; and as the skeleton and espe- 

 cially the skull is of most direct importance to the zoolo- 

 gist and palaeontologist, and as its form determines, as it 

 were, all other organs ... it seems to be that on which 

 election should fall for the fuller treatment." From this 

 opinion we disagree in toto. If the space allotted for the 

 subject is insufficient, it must be a fault of the general 

 management of the " Encyclopaedia." If the skull " deter- 

 mines, as it were," all other organs, then the study of ana- 

 tomy is on a very different footing from that on which it 

 seems to stand. By a glance at the earlier volumes of the 

 work, in which, as in the case of the article " Anatomy," 

 by Prof. Turner, apparently unlimited space is allowed to 

 the author, we come to the conclusion that there is no 

 fault in the editorial department, in this direction at least. 

 As to the " determining " influence of the skuU the true 

 relationship of three groups of birds — the woodpeckers, 

 toucans, and barbets — which will be found explained 

 below, is quite sufficient to demonstrate how unwarranted 

 is the assumption. 



In 1867 Prof. Huxley propounded a classification of 

 birds, not entirely, but mainly based on the nature of a 

 portion of the palatal region of the skull. This valuable 

 addition to ornithological and zoological literature has 

 given a great stimulus to more minute investigation of 

 avian structure. It brought to light many new facts, and 

 placed prominently forward others previously too much 

 neglected. The classification was, however, only an arti- 

 ficial one, for, according to that author's own words in the 

 article " Biology " before us, " in an artijicial classifica- 

 tion some prominent and easily observed feature is taken 

 as the mark of resemblance or dissemblance." The fea- 

 tures employed in this case were two — the fusion or non- 

 fusion of the maxiUo- palatine plates of the maxillary 

 bones, and the shape of the vomer. In a hobby-run-wild 

 manner, Prof. Parker, in his article "' Birds," has further 

 elaborated this artificial arrangement to a degree which, 

 more than anything else, demonstrates its untenability. 

 He begins by dividing the " Carinatae " into two sections, 

 firstly, the Dromaeognathae {Tinamous), and secondly 

 all the others ; because in the Tinamous the vomer is broad 

 behind and interposes between the pterygoids, the pala- 

 tines, and the basi-sphenoidal rostrum (which, however, is 

 Vol. XIII. — No. xz^ 



also the arrangement in some of the penguins at least.) 

 Among the other carinate birds, Prof. Huxley's divisions 

 are retained, except that the woodpeckers are removed 

 from the .Egithognathae to form an independent group of 

 equal importance with them, the Saurognathas ! The 

 DesmognathiE (Huxley), we are told, do not form a well- 

 collected group, and Prof. Parker does good service by 

 indicating the different ways in which desmognathism 

 may be produced. 



According to this classification, there are some so great 

 anomalies, when it is looked at from the aspect based on 

 the totality of the morphological resemblances in the 

 bird-class, that it is certain that the palate, per sc, is in 

 reality of secondary importance in the determination of 

 the relationships of many birds. 



For instance, according to Prof. Parker, the Woodpeckers 

 iPicidcE) form a main division (Saurognathae) of the non- 

 desmognathous carinate birds, at the same time that the 

 Toucans [Ramphastida), together with the Barbets {Capi- 

 tonidcc) form part of a minor section (Coccygomorphae) 

 of the desmognathous birds. In other words, they would 

 be made to have as little to do with one another as they 

 well can. Now the structure of the rest of the body, 

 other than the head, tells quite a different tale. From the 

 form of the feathers and the pterylosis, there being no after- 

 shaft, a tufted oil-gland and quite a characteristic distri- 

 bution of the peculiarly narrow feather-tracts ; from their 

 osteology, the sternum and other bones being almost 

 identical in all of them ; from the anatomy of the ali- 

 mentary canal, in which the colic c^eca are absent ; 

 from the arrangement of the toes in the scansorial foot ; 

 from their myology, in which they are identical when dis- 

 sected, muscle by muscle, and different in points from all 

 other birds, it is certain that the three groups, viz., the 

 Woodpeckers, Barbets, and Toucans, are most intimately 

 related, and have not, in reality, a family difference be- 

 tween them ; their dissimilarities — the Toucans and Bar- 

 bets merging into one another — leading to their being 

 arranged in two sub-families. 



As another example of the different teaching of the 

 artificial and the natural classifications, the Swifts 

 {Cypselidce) ^di the Humming Birds {Trochilidce) may 

 be referred to. These two groups, from the details of 

 their internal structure when examined one by one, are 

 most certainly related as intimately as are the Wood- 

 peckers with the Toucans. There is, in fact, not a family 

 difference between them, and yet, from their palates, Pro- 

 fessors Huxley and Parker place them in quite different 

 divisions, because the vomer is truncated in the one and 

 pointed in the other. 



We think that we have said enough to show that the 

 structure of the skull does not alone suffice to determine 

 the mutual affinities of birds, the head in them being 

 subject to rapidly developing peculiarities which are asso- 

 ciated with their habits of life. 



With the exception of the skeleton, the rest of which is 

 described in fair detail, Prof. Parker devotes but few 

 columns of his article to the organs, muscles, vessels, 

 and ner\-es ; he in most cases quoting verbatim from 

 Prof. Huxley's " Anatomy of Vertebrated Animals." 



Prof. Newton's portion of the article " Birds " forms a 

 valuable memoir on the topics he discusses. The ele- 

 gance of the style, and the careful manner in which the 



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