i68 



HODGE. 



EXPLANATION OF PLATE VIIL 



Normal Daily Fatigue. — Birds and Bees. 



Fig. 6. Morning. Portion of field from 3d brachial ganglion of English sparrow, 

 killed December — , '91, at 7 A.M. Osmic acid, i %, 2 hrs. 



Fig. 7. Evening. Field from corresponding ganglion of English sparrow, killed 

 same day (as Fig. 6), at 7.30 p.m. Like preparation with Fig. 6. 



Figs. 6 and 7 demonstrate extreme daily fatigue with probably some lack of food. 

 The queer-shaped clear spaces in Fig. 6 are seen to be replaced to a great degree in 

 Fig. 7 by faintly outlined, irregular vacuoles. Nuclei (Fig. 7) appear shrunken, as 

 in cases of electrical stimulation. 



(Occipital cortex of pigeons. April 28, '91; killed at 5.30 

 a.m. and 7.30 p.m. Corrosive sublimate, 40° C. 4 hrs. 

 Sections 3 m thick. Gaule's stain, on the shde. 

 Figs. 6, 7, 8, and 9, camera lucida drawings, magnification Zeiss, oc. 6, obj. 2 mm., 

 oil immersion (= X 750 diameters), apochromatic system. 



Median subdivision antenary lobe of brain of honey bee. 



Taken June 10, 6 a.m. and 7.30 P.M. 

 Osmic acid \ %, 2 hrs. Sections 3 m thick, stained in slide 



with Gaule's quadruple stain. 

 Camera lucida drawings, under Zeiss, oc. 8, obj. 2 mm., oil 



immersion (= X 1000 diameters). 

 Cerebellum of swallows killed 5 A.M. and 8 p.m. 

 Corrosive sublimate, with Gaule's stain. 

 Camera lucida drawing, with Leitz, ^^ oil immersion, obj. 

 oc. 3 (= X 965 diameters). 



Fig. II. 

 Fig. 10. 



Morning. 

 Evening. 



Fig. 13. Morning. 

 Fig. 12. Evening. 



