ON THE WEIGHTS OF THE ABDOMINAL AND THE 

 THORACIC VISCERA, THE SEX GLANDS, DUCTLESS 

 GLANDS AND THE EYEBALLS OF THE ALBINO RAT 

 (MUS NORVEGICUS ALBINUS) ACCORDING TO 

 BODY WEIGHT 



SHINKISHI HATAI 



The Wistar Institute of Anatomy and Biology 



TWELVE CHARTS 



Complete quantitative data on the various anatomical com- 

 ponents of the body are important not only for the study of 

 growth, but also for cross reference. A lack of such reference 

 data interferes in many cases with a clear recognition of altera- 

 tions which are taking place in the animal body under various 

 experimental conditions. Fortunately the following data on 

 the growth of the albino rat are already available : 



Growth of body in weight in respect to age (Donaldson '06) 

 and body length (Donaldson '09) ; weight of the brain and spinal 

 cord (Donaldson '08) ; weight of total amount of blood and hemo- 

 globin content (Chisolm '11), the growth of the head, trunk, 

 extremities, skin, skeleton, musculature and viscera in weight 

 according to age (Jackson and Lowrey '12) ; and finally the growth 

 of the dry substance in the albino rat (Lowrey '13). Besides 

 these we have several other series of data on the albino rat, 

 though not so comprehensive as those just cited. 



T];ie addition of the present data on the weight of individual 

 organs to the records above cited will make available observa- 

 tions on nearly all the important anatomical components of the 

 albino rat in a form useful either for the study of growth or for 

 cross reference. Indeed in no other mammal are such adequate 

 data available at the present moment. 



Since the object of the present paper is to report the objective 

 findings, mainly for reference purposes, many interesting points 



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