530 



SCIENCE. 



[N. S. Vol. IX. No. 218. 



nized authority and published by a reputable 

 firm. He may find that the book treats the 

 subject iu a more satisfactory maimer than the 

 text he has been using, and hence be led to 

 change. Or, if he cannot adopt the new book, 

 he may learn from it much that is inspiring and 

 suggestive of better methods of teaching. There 

 are far too many teachers, however, who, hav- 

 ing to give instruction in several subjects, have 

 not become especially proficient in any one and 

 are not fitted by experience and training to be 

 competent judges of the merits of different 

 texts. Zoology is one of those studies which 

 are usually ' lumped ' together and put into the 

 hands of the 'teacher of science,' who, more 

 often than not, is a physicist or a chemist by 

 training and, consequently, not likely to be 

 qualified to select a good text-book in zoology. 

 Too often is the choice determined by the scien- 

 tific reputation of the author, who may be of 

 undisputed ability as an investigator, but not 

 successful in his method of presenting his sub- 

 ject ; or by the business enterprise of the book 

 agent. Hence, it behooves those who are inter- 

 ested in raising the grade of instruction in the dif- 

 ferent scientific branches to exercise a careful 

 watch to prevent, if possible, the introduction of 

 text-books, and especially such as are elemen- 

 tary, which are faulty in method and inaccurate 

 in the statement of facts. There is no reason 

 why a new text-book should be issued unless it 

 present the subject by a better method and be a 

 distinct advance over those already published. 

 This elementary zoology "contains an ac- 

 count of a few types selected from the chief 

 groups of the animal kingdom, followed and 

 accompanied by a consideration of some of the 

 more general conclusions of biology." The 

 author adopts the very commendable plan of 

 treating the types in the ascending order, be- 

 ginning with a discussion of protoplasm and 

 the amoeba. The fifteen chapters of the book 

 deal with the unicellular animals ; hydra ; earth- 

 worm ; crayfish; cockroach; metamorphoses 

 of insects ; pond mussel ; snail ; frog ; skeletal 

 and integumentary structures of vertebrates ; 

 the egg, sperm, and development of the chick ; 

 morphology of organs ; morphology of tissues ; 

 class:£caticn ; classification of animals. The 

 most if t.hcs<ei epics are discussed with a toler- 



able degree of clearness, although paragraphs 

 are not infrequent which must be read more 

 than once before the meaning is grasped. 



It is questionable whether an average high- 

 school pupil could comprehend the author's 

 treatment of the morphology of the skull and 

 the development of the chick. The first cannot 

 be understood without much elaborate dissec- 

 tion and comparison of specimens, nor the 

 second without the use of sections, and the re- 

 construction of the latter either into a model 

 or iu the imagination is not within the capacity 

 of the beginner. 



There are so many grammatical and typo- 

 graphical erroi's that one is forced to believe 

 that the book was carelessly written and hastily 

 printed. For instance, a singular verb is not 

 infrequently burdened with a plurality of sub- 

 jects. The unbiased reader has his choice be- 

 tween ' spermathical ' and ' spermathecal ' pores 

 in the earthworm. Hydra is figured as con- 

 taining ' interstital ' cells and ' chromatphores,' 

 and anodon as having a 'coelome.' Several 

 figures, e. g., 8 and 9, do not tally with their 

 descriptions. Modifications of Maupas' figures 

 of the conjugation of vorticella are given, but 

 no description of the process accompanies 

 them. The directions for preparing dissections 

 are not always accurate. On p. 23 it is stated 

 that ' when an earthworm is opened by a median 

 incision along the back, and the flaps of skin 

 turned back, the entire anatomy is revealed.' 

 The student will find it necessary to do more 

 than this before he will discover the nervous 

 system. Again, on p. 63, 'when the mantle 

 flap of one side is removed the structures shown 

 in Fig. 29 are brought into view.' The pupil 

 who accepts this statement in good faith will 

 look in vain for the liver, pedal ganglion, con- 

 nectives and commissures shown in the illus- 

 tration. An anodon shell wdth the lines of 

 growth running ' parallel with the long axis of 

 the shell ' (p. 62) would be a prize for any con- 

 chologist. The explanation of the gaping of 

 the mussel shell after death (p. 62) has the ad- 

 vantage of novelty, if not of verity. It is in- 

 teresting, too, to learn that the snail is a sym- 

 metrical animal, that its radula bears calcified 

 teeth (p. 68) and that the blue color of its blood 

 is due to the presence of ' hsencyanin,' p. 70. 



