October 28, 1921] 



SCIENCE 



411 



are of especial value for those laboratories in 

 ■which these types are used to supplement 

 human material. 



The unavoidable difficulties of the study of 

 the nervous system are further increased by an 

 unnecessarily cumbersome nomenclature. Ran- 

 son has followed in the main the B. N. A. sys- 

 tem of terms, wisely using English forms of the 

 names in most cases. This system has at least 

 the merit that it is possible to find out exactly 

 what its names mean. Like nearly all other 

 recent anatomical writers, he departs from this 

 system in some respects (.e.g., dorsal and ven- 

 tral for posterior and anterior. Pending the 

 international revision of the B. N. A., which 

 is perhaps more urgently needed in neurology 

 than elsewhere, it is desirable that certain 

 other changes be widely adopted. The " pons " 

 of the B. ISr. A. is a hybrid monster, for 

 whose continued existence there is no justifi- 

 cation, anatomical, physiological, embryologi- 

 cal or comparative. Other similar infelicities 

 might be mentioned. 



As indicated at the beginning of this review, 

 the serious study of the nervous system can not 

 proceed far without practical work, and Ran- 

 son's book is so organized as to follow the 

 natural sequence of laboratory study. A brief 

 laboratory outline is included in the final 20 

 pages. 



The author has attempted to include within 

 the covers of one book all that the medical stu- 

 dent requires for his guidance in a first course 

 on the anatomy of the nervous system, and this 

 task has been well done. That this plan is very 

 acceptable to the student, there can be no ques- 

 tion, but in the reviewer's experience this is not 

 an unmixed benefit. With a manual of this sort 

 in his hands it is the very exceptional student 

 who can be induced to consult the atlases and 

 larger works of reference and the periodical 

 literature which he must learn to use if he 

 would win an adequate preparation and the 

 proper outlook for successful work in neu- 

 rology. The question may be raised whether 

 from the pedagogical standpoint the symmetry 

 and completeness of this work are, after all, 

 really advantageous. 



C. JuDSON Herrick 



SPECIAL ARTICLES 

 A SIMPLE APPARATUS FOR MICRO-MANIPU- 

 LATION UNDER THE HIGHEST MAG- 

 NIFICATIONS OF THE MICROSCOPE 



The microdissection and microinjection of 

 marine ova and of animal and plant cells have 

 hitherto been carried out by means of 

 Barber's^ pipette holder, an instrument pri- 

 marily intended for the isolation of bacteria. 

 Barber's instrument had the big advantage 

 over other similar mechanisms in that it 

 enabled one to manipulate needles in a drop 

 hanging from a coverslip suspended over a 

 moist chamber. This eliminated all obstacles 

 between the objective and the coverslip, there- 

 by permitting the use of high-power objec- 

 tives. 



The method of making the glass micro- 

 needles and pipettes is described in full in 

 Barber's various papers dating from 1904 to 

 1914 and in a pajjer of mine- in which the 

 application of the method to microdissection 

 is given. 



The principle involved in Barber's appara- 

 tus is a carrier pushed along a gi'oove by a 

 screw at one end. By having a series of three 

 carriers built up on one another, each travel- 

 ling in a difl^erent direction, movements in any 

 one of three dimensions may be imparted to 

 a needle clamped on the top carrier. It is 

 difficult to construct this instrument in such 

 a way that each movement can be maintained 

 in a precise focal plane. Even when skilful- 

 ly made, wear and tear in time renders the 

 movements jerky and undependable. 



The instrument described in this paper 

 has the following advantages over Barber's: 

 (a) simple construction, (6) absence of any 

 lost motion no matter how long the device 

 is used, (c) accurate and constant control of 

 the movements of the needle or pipette tip 



1 Barber, M. A., 1904, "A new method of 

 inoculating mieroorganisms, ' ' Jour. Kans. Med. 

 Soc, IV., 487; 1914, "The pipette method in the 

 isolation of single microorganisms and in the inocu- 

 lation of substances into living cells, ' ' The Philip. 

 Jour. Sc, Sec. B, Trop. Med., IX., 307. 



2 Chambers, R., 1918, "The microvivisection 

 method," Biol. Bull., XXXIV., 121. 



