104 



NA TURE 



[June i, 1905 



cofnpfess his"arronn^tmduly. - As aTiratter of fact tiie 

 whole history has been crowded into something lesS' 

 than eight and twenty pages, including illustrations ! 



This condensation is evident throughout each of the 

 chapters so far noticed, and probably accounts for the 

 absence of anything in the shape of an historical 

 review of the evolution of our knowledge of these 

 obscure groups. Surely this is to be regretted, inas- 

 much as this is a volume which will serve as the main 

 source, of information for many generations of 

 students ; and it would be well to place before them 

 some idea of the laborious and patient work which 

 has been spent by others in building up the knowledge 

 which is theirs to-day. Such a review would serve a 

 double purpose. It would keep alive the memory of 

 those whose names are all too soon forgotten, and it 

 would serve as an incentive to further work. 



Probably this survey would not have been wanting, 

 but for the fact that some two hundred and eighty of 

 the seven hundred and twenty-seven pages which mak' 

 up the book are devoted to the introduction on fishes ! 

 This is not as it should be: on this account serious 



penetrating into Holothunans two hfths 

 size. From the " Cambridge Natural Hi^torj. 



injury has been done both to the chapters which pre- 

 cede it and those which follow. Much of this intro- 

 duction could have been dispensed with, inasmuch 

 as matters of a purely physiological import are 

 now included, and these are outside the scope 

 of this volume. Lengthy as it is, it is vet 

 incomplete. Morphological questions that should 

 have found a place here are either ignored or dis- 

 missed in a few lines. If these had taken the room 

 of the matter to which we object some justification 

 might have been pleaded for the condensation of the 

 exceedingly valuable chapters which we have just 

 noticed. Vet, in spite of these drawbacks, this intro- 

 duction will prove most valuable to those who use 

 this volume as a text-book, and there is no doubt 

 but that it will be widely read and highlv valued in 

 the various^ science schools throughout the kingdom. 



It is a pity that more figures of larval fishes were 

 not given in this introduction, designed to illustrate 

 the remarkable transformations which some species 

 especially undergo from the time of hatching to 

 maturity. 



NO. 1857, VOL. 72I 



— i^-Te^a^d^a the CyclDstomata it is curious that no 

 mention is made of the extraordinary slime-secreting 

 powers of the Myxinoids. True, he refers to " a row 

 of mucous secreting sacs ^long each side of the body," 

 but this scarcely does justice to the case ; inasmuch 

 as an instance is on record of a single individual 

 which, placed in three or four cubic feet of water, 

 converted the whole into a jelly-like mass, which could 

 be lifted out with a stick ! The specific name of 

 Myxine glutinosa has reference to the old belief that 

 the fish possessed the power of turning water into 

 glue. 



Prof. Bridge solves the difficulty as to the syste- 

 matic position of Pateospondylus by placing them in 

 a sort of limbo designated an " appendix to the 

 fishes." ' 



In this same appendix it is somewhat surprising to 

 find not only the Ostracoderms, but the .'\rthrodira ! 

 .'\s touching the former Prof. Bridge may claim that 

 he errs, if erring he is, in good company, since so 

 eminent an authority as Dr. Smith Woodward refuses 

 to admit these " bones of contention " into the class 

 Pisces. But we object to the hesitancy displayed by 

 Prof. Bridge ; he will neither call them fishes nor 

 allow them to rank as a separate class (Agnatha), as 

 Dr. Woodward has done. But surely there can be 

 no question as to the class, at least, to which the 

 Arthrodira belong? According to the most recent 

 \ lews they are to be regarded as Dipnoans. 



In spite of these drawbacks Prof. Bridge's contribu- 

 tion to this volume is a valuable one. He has brought 

 together a vast amount of information, much of which 

 IS the result of his own researches. Where he has 

 had to draw upon the work of others he has for the 

 most part selected of the best. Our chief complaint 

 IS that he is so meticulously exact. 



The Teleostei, from a systematic point of view, are 

 described by Mr. E. A. Boulenger, and he has brought 

 to bear upon this most difficult task an unrivalled 

 knowledge, tempered with rare skill and judgment. 

 The classification which has been generally in use 

 in this country for the last thirty years is now replaced 

 I \ line which aims at being phylogenetic — the true 

 1 t-i-; of all systematic work. .Although we believe 

 Mr. Boulenger has improved on this arrangement in 

 • tme minor details since passing the final proofs of 

 Ills work some three years ago, it may be accepted 

 is practically representing his views on this subject. 



.As he remarks, " Out of some 12,000 well- 

 established species of fishes known to exist at the 

 present day, about 11,500 belong to this order 

 (Teleostei). The classification of such an array of 

 forms is, of course, a matter of great difficulty, and 

 gives scope for much difference of opinion among 

 those who have attempted to grapple with the sub- 

 ject." The basis of this classification differs from that 

 usually employed in other groups of vertebrates, in- 

 asmuch as it rests on osteological characters, in so far 

 as families and higher groups are concerned. 



The reader of this notice may imagine, from our 

 ominous reference to dry bones, that Mr. Boulenger's 

 contribution is of the nature of a dull and tiresome 

 catalogue. We hasten to remark, therefore, that this 

 element is effectually masked by the introduction of 

 all the more important facts concerning the life- 

 histories of the various species which have come 

 within the author's province. These facts form most 

 fascinating reading, and will appeal to a large number 

 of people other than professed students of zoology. 

 Do fishes sleep? is a question often asked. .Although 

 answered in the afiirmative some eight and thirtv 

 years ago by Mobius, the fact has remained ever since 

 practically buried in the German publication in which 

 it appeared. Mr. Boulenger is apparently the first to 

 give it circulation in a text-book. A species of Wrasse 



