1920] HAUPT—FOSSOMBRONIA ' 321 



and the venter becomes 2 cells thick only after fertilization. The 

 first division of the fertilized egg is transverse, the upper segment 

 forming the capsule and the lower forming the foot. The second 

 transverse division separates the segment which is to form the 

 capsule from that which is to form the seta. A third transverse 

 division occurs in the uppermost cell, resulting in a tier of 4 super- 

 imposed cells. After this 2 vertical walls appear at right angles to 

 each other, followed by periclinal walls in the upper segment. 

 The author states that the capsule wall is normally 2 cells thick, 

 but shows a wall composed of 3 layers of cells in his fig. 61. Both 

 layers of the capsule bear annular thickenings. The mature elaters 

 reach a length of 150-300 /x, and are provided with a double spiral 

 thickening. Dehiscence is by means of four valves. 



Humphrey's account of the development of the antheridium 

 is vague, especially because no references to his figures are given 

 in the description. Two interpretations are possible. If the 

 second wall in the antheridium initial is transverse and is followed 

 by vertical divisions in the two uppermost segments, the develop- 

 ment is exactly like "what occurs in the majority of the Junger- 

 manniaceae," as his figure representing this stage is the same as 

 my fig. ii, except that the first vertical divisions result in an 

 octant of cells instead of the condition shown in fig. 15. If 

 Humphrey speaks of the initial as the dorsal segment resulting 

 from the first transverse division of the true initial, then the third 

 wall in the true initial is transverse instead of vertical, but the 

 situation according to this interpretation would be precisely the 

 same as that in Sphaerocarpas. 



At any rate, Humphrey's series of stages are not sufficiently 

 close to convince one that the situation in Fossombronia is radically 

 different from that characteristic of most of the other Jungerman- 

 niales, and inasmuch as no mitotic figures are shown to prove the 

 exact sequence of the first divisions in the initial, except for his 

 figures of cross-sections, it is possible to interpret the development 

 of the antheridium of F. longiseta as strictly normal. If Humphrey 

 is really familiar with the development of the antheridium in the 

 majority of the Jungermanniales as well as that of Sphaerocarpus, 

 and the difficulty in interpreting his account is merely the result 



