194 FIELD OATS. 



bracteoles inserted fore and aft on the floral axis below 

 the flower, and he has made out a good case in favor 

 of his view but perhaps not an unanswerable one." 20 

 Bentham " adds : " The search for homologies to the 

 palea and lodicules in the orders nearly allied to the 

 Graminece has met with but little success ; " and again, 

 " The palea and lodicules of Graminece may represent 

 perianth segments of an outer and inner series, though 

 I by no means pretend to assert it as a proved fact." 

 Again," " In all cases, the palea, whatever its origin, 

 is called upon in conjunction with the subtending 

 glume to perform more or less of the functions of the 

 deficient or absent perianth." 



It is to be noticed that the male and female repro- 

 ductive organs occur in the same flower, which is 

 therefore hermaphrodite. The stamens of oats are 

 to be looked upon as metamorphosed leaves, as in the 

 pine ; it seems probable, though not definitely proved, 

 that the pollen sacs are homologous with those of the 

 pine. The immature pollen spore is two-celled, as in 

 most other angiosperms, 23 and it is doubtful whether 

 there is any trace of a prothallium. This stage in the 

 life cycle of the plant, which is so marked in the moss 

 and liverwort, far less prominent in the fern, reduced, 

 if it can be considered present at all, to but a cell or 

 two in the pine, is in this plant probably entirely sup- 

 pressed. 



Attention is called to the fact that the ovule is not 



20 Bentham, Notes on Gramineae, Jour. Linn. Soc., xix, p. 23. 



21 L. c., p. 24. 



' 2 L. C.,p. 2 5 . 



23 Cf. Strasburger, Neue Untersuchungen, p. 5, 



