234 S. SAGUCHI 



in order to exhibit the basal corpuscle, varies according to the 

 grade of differentiation. This is an advantage, and, at the same 

 time, a difficulty, of that technic. To speak more correctly: 

 whilej on the one hand, it enables one to judge the intensity of 

 its affinity for cell-constituents, the same constituent of the cell, 

 on the other hand, often presents a good deal of variety accord- 

 in.g to the degree of staining, which may give rise to misinter- 

 pretation. Not only the manipulation of staining, but also the 

 degree of matm'ation of haematoxylin-solution used has a marked 

 effect upon the result. An especially important factor in this 

 staining is the method of fixing and the quality of fixative. 

 For example, in preparations from materials perfectly fixed in 

 riemming's fluid the mitochondrial filaments stain deeply, where- 

 as the basal corpuscles remain unstained ; in poorly-fixed Flemming 

 and in the sublima+e-material, on the other hand, it shows an 

 inverse staining capacity. 



So far as can be seen from my preparations, the basal cor- 

 puscles may be classified according to their shape and position 

 as follows: 



1) Spherical or elliptical basal corpuscles which are situated 

 beneath the cuticle; these forms are met with in the gill (fig. 5, 

 lateral cells), foot (figs. 1-3) and intestine (figs. 6-8) of Anodonta, 

 in the intestine (fig. 9) and hepatic duct (figs. 10, 11) of Helix, 

 in the intestine of Limax and Lumbricus, in the pharynx of 

 Rana, Bufo and Triton (figs. 46, 49), in the gall-duct of Rana 

 (fig. 57), and in the trachea of Trigonocephalus, of the mouse and 

 rat (fig. 92). Such cases as this are found in the description 

 and figures of the following authors who studied the intestines 

 of invertebrates: Apathy ('97, typhlosole of Anodonta, Lenhossek 

 ('98, middle intestine of Anodonta), Heidenhain ('99, intestine of 

 Helix), Gurwitsch ('01, intestine and mouth of Lumbricus), 

 Holmgren ('03, pharyngeal pouch of Lumbricus), Erhard '10, 

 typhlosole and hepatic duct of Anodonta), and Kolacev ('10, in- 

 testine of Anodonta). 



The corpuscles found by Engelmann ('80) in the intestine of 

 Cyclas and Unio, and named by him 'Fussstlicke' may, as al- 

 ready stated by Studnicka ('99), be identified with the basal 

 corpuscles. Heidenhain ('99) describes and figures lozenge- 



