nEVUE BRYOLOGTQUE 79 



+ 



and figure given by Hooker *. In the plants seen by the writer, 

 the capsule was vertical in position, lying in the axis of the seta, 

 and the slit appeared cither on the posterior side of the capsule 

 (i. e., the side nearest the involucre) or was lateral in position. ^ 

 As a rule, a second slit begins to be formed on the opposite side 

 to the first one, hut the former is usually incomplete, and only 

 extends a short distance from the apex of the capsule (fig. 1, E.)- 

 The capsule wall, on either side of the complete slit, becomes 

 rolled back, exposing the mass of spores and elaters ; the elatcrs 

 show hygroscopic movements, twisting about and loosening the 

 mass, so that the spores gradually fall out. According to 



i 



m 



the young capsule , but in the unopened capsules which the 

 writer has examined, nothing could be seen of any such lines. 



The SPORES are small, nearly spherical (about 16 fx in diameter), 

 and have a thin coat, covered with granules (Fig. A, IT.)- The 

 ELATERS are remarkably long (about 500 jx in length and 10 y. in 

 greatest ^vidth) and are arranged paralled with the long axis 

 of the capsule ; many of thera are attached by one (usually the 

 upper) end t^ the inner surface of the capsule-wall. 



The genus Monoclea has usu'ally been placed by systematists 

 in the Jungermanniaccce, but in many respects it differs from 

 this group and agrees with the Marchantiacese. Lei I gebf called 

 attention to the striking similarity which the male receptacle 

 bears to that of various Marchautiacea}, and Campbell-f- has 

 suggested that this genus should be removed from the Junger- 

 manniacete and placed in the Marchanliac'ese, near Targioma. 

 According toCau>pbell, the affinities of -Vonoc/^a are with the lower 

 Marchantiacese, where the archegonia are borne in a group on 

 the thallus and no definite receptacle is developed. The points 

 ... which Monudca resembles the typical Marchantiacea^ and 

 differs from the majority of the Jungermanniacea^ may be sum- 

 marised as follows : (1) the presence of two kinds of rhizoids ; 

 (=>) the structure and d(;velopment of the male receptacle ; (J) 

 the development of the anlheridium, especially in the formation 

 (,f several transverse walls previous to the first vertical divisions; 

 (4) the presence of six rows of neck-cells in the archegonium. 



* Musci exotici (1820), Vol. II, Tab. I7i. 



t Untersuchungen iiher die Lebermoose, tJefl III, p OS. 



t Loc. cil., Ilept vi., p. 132. 



4- The Svstematio Position of the Genus Monoclea Botanical Gazelle, 

 Vol. 25, mS, pp. 272-4. 



in 



