158 M. R. KING 



of the anterior papillary muscle. Having reached the anterior 

 ventricular wall, the right branch breaks up into the terminal 

 network of the right ventricle (Purkinje fibres), similar to that 

 found in the left ventricle. However, since the first point of 

 branching is on the anterior wall it necessarily follows that in 

 order to reach the septal wall the network must needs pass by 

 way of the conus anteriosus, of the inferior and posterior junction 

 of the anterior and septal walls and of the moderator band when 

 this latter connection is of goodly size as is often the case (fig. 4). 



Special attention was paid to the flow of the injection mass 

 during its course along the right crus to see if any branches were 

 given off between its point of origin from the crus commune 

 and its point of branching at the base of the anterior papillary 

 muscle. In no place along its course was a single branch given 

 off. Curran mentioned a branch as being given off just as the 

 right crus makes the turn passing along the moderator band. 

 This branch he stated supplies the conus arteriosus, but DeWitt, 

 in her dissections, was unable to demonstrate any branches 

 passing from the right crus. False tendons are not so numerous 

 as in the left ventricle. They all seemed to carry fasiculi of the 

 system, however, even the finest threads being injected. 



As mentioned above the left crus of the bundle branches on 

 the left septal wall at a point half-waj^ between the aortic orifice 

 and the apex but in the case of the right crus no branching is 

 found until the anterior wall of the right ventricle is reached. 

 Hence there is a decided difference in the length of the two 

 septal crura, the right varying somewhat according to the length 

 of the moderator band while the left remains more constant. 

 The right crus as measured from crus commune to the point of 

 branching was found to average 7.5 cm., while the left crus 

 measured in like manner averaged but 4 cm. The course of 

 the right crus, especially from its point of origin to its turning 

 point on the moderator band is signified by its decided oval or 

 cylindrical form and its more deeply imbedded position as 

 compared with the flatter and more superficial left crus (figs. 

 10-11). As it makes the turn necessary to cross the moderator 

 band it flattens out somewhat thus causing the appearance of an 



