4IO MAINE AGRICUIvTURAI, EXP1;rIMENT STATION. I912. 



As shown in figure 454, the longitudinal ridges are very high 

 and broad in this part of the oviduct. A better idea of the 

 development of these ridges can be obtained from figure 462. 

 This figure is drawn with the same magnification as figures 457, 

 458, 468 and 469. It is seen at once that these ridges are much 

 higher and broader here than in any other part of the oviduct. 

 The major portion of this increase in the size of the ridges is 

 due to the greater development of the tubular glands. These 

 glands form a distinct tissue layer between the inner layer of 

 connective tissue and the epithelium. 



The muscular layers in the albumen region are somewhat 

 thicker and the bundles are much better segregated into definite 

 layers than in the funnel region. However, the musculature 

 of this region is much less developed than in the parts of the 

 oviduct posterior to it. This point is clearly seen by comparing 

 figure 462 with figures 468, 469 and 473. The slow movement 

 of the egg through this part of the duct is evidently associated 

 with its weak musculature. 



As shown in transverse section (figure 462) the fibers in the 

 outer layers of muscles, run in general in a longitudinal direc- 

 tion through the oviduct, but at the same time they take a 

 slightly spiral course. That the inner muscular layer runs in a 

 circular direction is evident from figure 462. These sections 

 have been cut very nearly transverse to the long axis of the 

 oviduct. Consequently the long fibers seen in the inner mus- 

 cular layer certainly run in a transverse or circular direction. 

 The spiral course of the fibers in the outer muscular layer 

 rather obscures the fact as to their essentially longitudinal 

 nature. These same facts have been brought out by Miss 

 Curtis ('10) in connection with the study of the ligaments of 

 the oviduct. She has shown by means of very careful dissec- 

 tions that the outer muscular layer, which is continuous with 

 the musculature of the ligaments, is longitudinal and that the 

 inner layer consists of circular fibers. These facts are opposed 

 to Sacchi's statement that the internal muscular layer is longi- 

 tudinal and the outer circular. Sacchi says (p. 297) in regard 

 to the funnel region, "L'epithelio che le ricopere e pure cylin- 

 drico e munito di ciglia ; il connessivo e attraversato da vasi, e 

 verso 1 'esterno vi sono frammisti fasci muscolari longitudinali 

 isolati, circondati da muscoli circolari e poi dal connessivo 



