True, Notes on the Ph^'siology of the Sporoplu-te etc. 43 



because of the greater resisting action of the solid masses of 

 tissued formed. 



Another fact observed ma}^ serve to explain the great effi- 

 ciency of this protecting structui^e. Although torn awa}^ from it.s 

 phice of growth at an eaiiy stage in the life of the sporophyte, 

 the cells of the calyptra are found to be living until shortly l)e- 

 fore it is ruptured by the increased size of the enclosed capsiile. 

 Having no organic connection during this long ])eriod with any 

 sonrce of food <<upply, it must maintain itself independentl3\ 

 Since each cell contains a good number of chloroplasts, this me- 

 thod of Support is easily surmised. The source of the neccessary 

 steady water snpply is doubtfnl. On removing the calyptra from 

 the sporophyte, minute drops of water were usually seen adhe- 

 ring to the sporophyte, and the examination nnder low magni- 

 tication of the sporophyte bearing the calyptra in position re- 

 vealed the presence of water more or less ülling the Upper part 

 of the calyptra. AVhether this water is excreted by the sporo- 

 ])hyte and maintained in place by the calyptra, or whether the 

 calyptra itself has the ability to condense or absorb water through 

 its much folded outer surface, can hardly be said. At all events, 

 the calyptra is doubtless supplied with the substances and con- 

 ditions necessary for carbohydrate formation, and for its nearly 

 indopendent, temporary nutrition. Thus in the developing spo- 

 rophyte, three organicalli unconnected structures are present, 

 each to a considerable extent capable of independent nutrition. 



In Mniiim^ growing on the damp leaf-mould in the woods, 

 the danger of desiccation is minimal and the calyptra seems to 

 reilect this in its structure. It is pointed at the distal end and 

 widens somewhat rapidly toward the base. There is no close 

 clasping of the seta at the base. and the calyptra fall off at a 

 much earlier stage than in Fiinaria. It seems to me that a 

 thorough study of the structure of the calyptra and its ecological 

 relations to the sporoph^^te offers an interesting problem in ways 

 and means in Archegoniates. 



Another question of some interest was raised in connection 

 wirh this studv. It was noted that in the voung Stades of the 

 FHiiaria spor(jphyte. the distal end, containing the regions of 

 cell division and most of the zone of elongation. was thrust into 

 the calyptra to the very extreme of the long, beak-like portion 

 and was not withdrawn to the capacious sac-like part un- 

 til the enlargoment of the capsular rudiment was abotit to begin 

 or was already to be traced. This withdrawal of the end of the 

 sporophyte to the more roomy portion of the calyptra could be 

 seen in progress before any noticeable enlargement of the latter 

 had taken place. Usually, however, the curvature of the seta 

 began contemjjoraneously with the beginning of the withdrawal. 

 In what way this withdrawal was effected was not easily ex- 

 l)lained. It seems probable that the inner surface of the beak- 

 like portion of the calyptra is moist and offers little friction to 

 the smooth surface of the slender sporophyte. (5j As the cur- 



