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7. Lowne, B. T. 1893-1895. The Anatomy, Physiology, Mor- 



phology and Development of the Blow-fly. Pp. 408-409. 



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chez les Blattidae et les Gryllidse. Compt. R. Acad, de Sc. 

 Paris, T. 123. Pp. 271-273. 



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306-312. 



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Explanation of Plates. 



Plate V. Sections through the proventriculus of Gryllus pennsyl- 

 vanicus. All greatly enlarged. 

 Fig. 1. Longitudinal section through the median denticles. 

 Fig. 2. Transverse section passing through two folds of the 



anterior division of the proventriculus. 

 Fig. 3. Surface view of a portion of one of the dental folds 



showing the chitinous partition and four of the transverse 



rows of teeth. 

 Fig. 4. Transverse section of proventriculus passing through the 



median denticles. 

 Fig. 5. Transverse section of fold cut in the region of the lateral 



denticles. 

 Fig. 6. Lateral view of two adjacent inner barbated lobes. 



br. = Bristles of anterior division of proventriculus. 



ch. p. = Chitinous partition between dental folds. 



c. m. = Circular compressing muscles. 



c. V. = Cardiac valve. 



ep. = Epithelium. 



i. b. 1. = Inner barbated lobes. 



in. = Intima. 



1. d. = Lateial denticle. 



1. t. = Lateral tooth. 



m. d. = Median denticles. 



