104 



SCIENCE 



[N. S. Vol. XLIV. No. 1125 



logical processes become the special object of 

 research. 



Less satisfactory than the experimental tech- 

 nique is the statistical treatment of the results. 

 Serious objection must be taken to the misuse 

 of the average. It is wholly misleading, for in- 

 stance, to give 22 as the average of the three 

 measurements, -f- 85, — 9 and — 11. This 

 figure is held to show that three so-called psy- 

 chopathic subjects, i. e., men who had been 

 intemperate, did not differ to any extent from 

 seven normal subjects. Really, the figures only 

 show that of three formerly intemperate sub- 

 jects one was far more sensitive than usual to 

 the depressing effects of alcohol on the eyelid 

 reflex, while the other two subjects resembled 

 one out of the seven normal men in showing 

 the stimulating effect of 30 c.c. of ethyl alcohol. 

 This and other measurements on the intem- 

 perate subjects serve to confirm the statements 

 made in their personal histories, that one was 

 unusually sensitive to the influence of alcohol, 

 while the others were less sensitive than usual, 

 not, it is probable, on account of psychopathy, 

 but through their former habituation to the 

 action of alcohol. In so far as any weight can 

 be attached to the apparently stimulating effect 

 of alcohol in these two subjects, it may have 

 been due to the satisfaction of a craving. 



This work is the first contribution to an in- 

 vestigation of the action of alcohol which it is 

 to be hoped may extend over many years and 

 go far to settle a number of obscure and diffi- 

 cult problems. I have ventured to call atten- 

 tion to certain points of methodology and 

 workmanship which seem to require reconsid- 

 eration because in such an investigation prin- 

 ciples and methods can not be too closely 

 scrutinized at the outset. The criticisms now 

 offered must not be allowed to obscure the 

 recognition of the great value and promise of 

 the work. 



W. H. R Rivers 



University op Cambridge 



Typical Flies — A Photographic Atlas of Dip- 

 tera, including Aphaniptera. By E. K. 

 Pearoe. Cambridge (England), University 

 Press, 1915. 



This royal octavo, bound in boards, contains 

 4 pages of preface, 4 pages of classification; 

 45 pages of half-tone reproductions from 

 photographs, comprising 155 figures represent- 

 ing 125 species distributed in various families, 

 including 4 species of fleas, and 3 fly habitats ; 

 concluding with 2 pages of index. Under the 

 figures are given technical name of the species, 

 common name, if any, length of body, wing ex- 

 panse, with brief data on habits and habitats. 



The book is intended to fill the place of a 

 pictorial elementary treatise. The plan is an 

 excellent one, but difficult of proper execution. 

 The author complains of the difficulties which 

 he encountered in obtaining suitable material 

 for photographic reproduction. Nevertheless, 

 the figures are all quite recognizable, which is 

 the main requisite to the success of the plan. 

 The feature of including habitat photographs 

 is commendable and might have been farther 

 pursued. 



There is no doubt that the wings and legs of 

 flies must be spread in order to photograph 

 them to the best advantage, but care must be 

 exercised to secure natural attitudes, just as in 

 the mounting of birds, mammals and other 

 animals. Otherwise the reproductions are not 

 true to nature but leave a marred image upon 

 the memory, which appreciably reduces facil- 

 ity of recognition of the species in its habitat. 



Recommendations made by the author in his 

 preface regarding methods of mounting are 

 open to objection. Aside from material for 

 photographing, and the proper setting of the 

 proboscis and hypopygium for study in certain 

 forms, the reviewer decidedly favors leaving all 

 flies in the natural attitudes assumed by them 

 in the killing bottle. Specimens too small to 

 be pinned with a No. 2 pin should be mounted 

 on minute wire elbows wound on No. 3 pins. 

 Only 34 to 39 mm. pins should be used, longer 

 sizes giving trouble in the standard-depth 

 cases. Great care should be taken not to get 

 the specimen too high on the pin, but to leave 

 sufficient room for grasping the head of the 

 pin with the thumb and finger without danger 

 of contact with the wings or other parts. 

 There should be left sufficient space on the pin 

 below the specimen for several labels, which 



