Monotropaceae with Reference to Ericaceae 47 



appeared glandular at the base of the ovary in P. secunda, P. 

 chlorantha, P. aphylla, but none in P. rotundifolia, P. elliptica, 

 and P. minor. 



In the Monotropaceae Drude says "Disc present, or replaced 

 by nectaries, rarely lacking." In Allotropa, according to Torrey 

 and Gray (77), it is minutely ten-lobed. The writer finds ten 

 slightly downward directed lobes; in Monotropa there are 8-10 

 downward directed nectaries; in Sarcodes* there are ten swell- 

 ings at the base of the ovary; in Pterospora Drude reports that 

 it is absent. 



In Schweinitzia there are ten lobes between the stamens. 

 Drude states that in the Pleuricosporeae the disc is entirely 

 lacking in Newberrya, Pleuricospora, and Cheilotheca. This 

 appears to be true of Pleuricospora but in Newberrya the writer 

 finds that ten nectaries are present at the base of the ovary, 

 very similar to those of Monotropa. No material of Cheilo- 

 theca could be obtained for examination. 



(4) In the Pyrolaceae and Monotropaceae the dehiscence of 

 the anthers follows one of these types. 



1 . Apical porous — with more or less developed tubes in Chima- 

 phila, Pyrola, Moneses, Sarcodes, Schweinitzia. 



2. Longitudinal — Allotropa, Pterospora, Pleuricospora, New- 

 berrya, Cheilotheca. 



3. Transverse — Monotropa. 



In the Ericaceae apical porous and longitudinal dehiscence 

 seem to be about equally distributed throughout the family 

 and even in the same group, i.e., in the Rhododendroideae-Ledeae 

 Bejaria and Ledum have apical porous, Elliottia and Clado- 

 thamnus longitudinal dehiscence of the anthers. Transverse 

 dehiscence of the anthers also occurs in the Ericaceae. The 

 group Arbutoideae-Andromedeae, according to Drude (12), has 

 pores or slits at the apex or transverse slits. 



(5) The Pyrolaceae and Ericaceae have tetrad pollen grains, 

 the Monotropaceae simple pollen grains. However Pyrola 

 secunda, a typical member of the genus, has simple pollen grains 

 so that even this distinction does not entirely hold true. 



* Drude reports no disc in Sarcodes; Oliver (58) that the disc is present. 

 The writer's material confirms the latter. 



