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NEW YORK STATE MUSEUM 



polygonal cells, which become rounded on the removal of 

 pressure^. 



Pedal gland 



The pedal gland (pi. 4, fig. 4, 5)^ is situated in the middle of the 

 basal part of the foot. It is a spongy-appearing mass, extending 

 about two thirds the entire length of the foot, with a central cir- 

 cular passage connecting with the exterior by an opening im- 

 mediately below the mouth, and sending forth numerous ducts to 

 all parts of the basal portion of the foot. Its office is to secrete 

 the mucus or slime, which the snail so abundantly exudes while 

 moving, and which when hardened by the air presents a glassy 

 appearance. 



enterochlorophyll 

 lecithin 

 oleic acid 

 In the alcoholic extract <j ^atty acids 



I / chlorin 



j ash / phosphoric acid 

 [ ' sulfuric acid 



In the ethereal extract, a trace of fat 

 ' sugar 

 globules (coagulating at 66- C.) 

 glycogen 

 sinistrin 

 hypoxanthin 



' potassium 

 sodium 

 calcium 

 magnesium 

 ash<! iron (traces) 

 manganese 



chlorin / 



phosphoric acid 

 I sulfuric acid 



Dr Griffith {Phys. invert, p. 115) names the following substances as being found in 

 the digestive gland of the Pulmogasteropoda: diastatic ferments, pancreatin, peptones 

 and sodium. 



In the aqueous extract 



1 Dr Levy {Zcit. hiol. 27:398) has separated the following substances from the 

 digestive glands of Helix pom'atia. 



