26 



NATURE 



[May II, 1876 



would bean immense advantage. Prof. Macalister heads 

 each page with the words, " Introduction to Animal Mor- 

 phology." In so doing he seems to have entirely over- 

 looked the fact that the object of the heading is to give 

 some notion as to what is to be found below it, and not the 

 title of the work itself. Why he has not followed the 

 ordinary method of placing on the top of one of each two 

 pages the subject of the chapter, and on the other further 

 detail, we are at a loss to understand, and suffer accord- 

 ingly in attempting to make any particular reference. 



The first seven chapters of Prof. Macalister's work are 

 on general subjects : protoplasm, general morphology* 

 histology, tectology (individuality and the formation of 

 organs), reproduction, and the distribution of animals. 

 There are certain statements in the last of these with 

 which we cannot quite agree. That Patagonia should 

 be entirely removed from the Neotropical Region and 

 placed together with the Southern Circumpolar Land in a 

 special Antarctic, seems very much at variance with 

 known facts. Why the Polar Bear should be only men- 

 tioned in association with the Nearctic Circumpolar Re- 

 gion ; the Aard-vark, Manis, and Manatee with the 

 Guinean ; the Catarrhine Monkeys with the Indian ; 

 Bennett's Cassowary with the Austrahan ; the Birds of 

 Paradise with the Indo-Malay, we are at a loss to 

 comprehend. 



In association with the doctrine of the origin of species 

 we are told that, " as a natural deduction from evolution^ 

 we have Dr. Haughion's law, that all structures are 

 arranged so as to give the maximum of work possible 

 under the given external conditions." This law is, how- 

 ever, a natural deduction from the theory of natural selec- 

 tion, not from evolution ; it not being evolution, per se, 

 but the struggle for existence which brings to the fore- 

 ground the most economical animal machinery. It may 

 also be mentioned that there are still wanting some im- 

 portant links in the chain of reasoning which explains 

 the diminution of organs, like the wings of birds, in 

 small islands. These seem to' be lost on account of the 

 reduction of the struggle for existence, mammals not 

 being on the ground to contest the field. Dr. Haughton's 

 law, therefore, no longer applies apparently. Why then 

 are the wings lost ? 



The classification adopted is that of Haeckel modified, 

 the Metazoa being primarily divided into the two sub- 

 series, Polystomata (Sponges) and Monostomata ; the 

 Coelenterata being removed from the Porifera, and in- 

 cluded with the other forms in which there is but one 

 aperture of ingress into the body-cavity. No very special 

 stress is laid on the vertebrate affinities of the Tunicata, 

 which are included in the sub-kingdom Vermes. Of their 

 development we read that " in Ascidia and Phallusia the 

 segmented yelk assumes its mulberry form, hollows 

 within, and appears as a spherical, cellular body (blas- 

 tula) ; a groove indents one side of this ; the lips of the 

 groove rise and close it in, except in one spot, and thus 

 the body becomes bicavitary, the dorsal groove contracts, 

 and the nerve ganglion develops either within it or in its 

 close vicinity. On a plane between the dorsal neural 

 cavity thus formed and the ventral space, a double row of 

 large cells appears, which extends into the tail, and forms 

 an axis for that organ. These cells resemble those of the 

 chorda dorsalis of Vertebrates, and have a similar relation 



to the neural and visceral cavities of the primarily bicavi- 

 tary body to that possessed by the dorsal chord. Upon 

 these phenomena, observed by Kowalewsky, Kupffer, and 

 others, is rested the theory of relationship of Tunicates 

 and Vertebrates, which is strengthened by the setting 

 apart here of a portion of the digestive canal for respira- 

 tory purposes." This quotation illustrates the condensed 

 manner in which the whole work is written and the way 

 in which single words are frequently modified to do the 

 duty of whole sentences. As a second illustration of the 

 same method when employed with reference to the sub- 

 kingdom Coelenterata, one in which name-coining has 

 arrived at a worse pitch even than in systematic botany — 

 the following sentence will suffice : — " The alternation of 

 generations may be binary (hydranth, gonophore, -f- hy- 

 dranth, gonophore, &c.), or ternary (hydranth, blastostyle, 

 gonophore, + /t, b, g, &c.), or quaternary (hydranth, 

 blastostyle, blastocheme, gonocheme, -f //, b, b, g, Sec.) ; 

 or even more complex if the hydranths be heteromor- 

 phic." The Mollusca are treated of between the Vermes 

 and Arthropoda, it being remarked of them that " their 

 structure can be easily understood by regarding them as 

 Vermes with no articulated appendages, modified by 

 unequal lateral development, and by a fusion of the 

 metameres," although "we know as yet of no absolute 

 passage forms or direct synthetic types." This being the 

 case, we cannot understand how each of these major 

 groups can be regarded as a sub-kingdom. 



The author, in his preface, regrets that, owing to the 

 long time that the work (written in 1873) has been going 

 through the press, he has not been able to introduce into 

 it references to recent discoveries, which explains several 

 important omissions. Notwithstanding this, we are con- 

 vinced that all zoologists will agree that the work is a 

 most valuable addition to the literature of general animal 

 morphology. 



OUR BOOK SHELF 



Introductory Text-book of Physical Geography. By 

 David Page. Eighth Edition. (Blackwood and Sons, 

 1876.) 



Introductory text-books on Physical Geography are 

 not numerous, and if we may judge by the calls for new 

 editions, this one is growing in favour. It certainly gives 

 in a short and handy form the most important facts of the 

 subject — ^and in the descriptive part it is merely a question 

 of the selection of the most important, and in this respect 

 we think the selection judicious, as indeed it would 

 appear to have been found. Dr. Page comes to Physical 

 Geography from the side of Geology, and his readers reap 

 the benefit of it, in the chapters relating to the structure 

 of the earth, and to the work of rivers, and to the positions 

 of mountain ranges, which are very good. In many other 

 respects too, the book is worthy of the support it receives, 

 the facts being told clearly, concisely, and for the most 

 part truly. 



We cannot help, however, drawing attention to one or 

 two points which we think would at least have been dif- 

 ferently worded if the author had approached his subject 

 from a physical side in his explanation of phenomena. 

 Thus we are told with reference to water, that " when 

 converted into steam it occupies 1,696 times more space 

 with a specific gravity of only "622." The only standard 

 of specific gravity mentioned is water at 62° F., and a 

 physicist might ask at what pressure is the steam .'' 



Again, we read, " the atmosphere being the medium 



