PLATE IV. 



Mesenchytrcetis setchelli sp. nov. 



Fig. I. Section through the penial bulb and pore, showing the long ducts 

 of the atrial glands opening near the pore. A band of circular mus- 

 cles surround the atrium inside the penial bulb. This figure is 

 held somewhat diagrammatic. 



2. Section through the upper part of the atrium, showing the entrance 

 of one atrial gland and the ducts of four other atrial glands. 



3. Atrium of sperm-duct with five atrial glands. Somewhat diagram- 

 matic. 



Mesenchytrceus franciscanus sp. nov. 



4. Section through the body in somite xii, passing through the large 

 accessory glands. The pores of the sperm-ducts, and the atrium, 

 etc. are cut by several sections posterior to this one. 



^b, 5c, 5(f, $e and 5/". Spermatophores in various stages of develop- 

 ment. 



(134) 



