THE BRACTS AND FLOWERS. . 33 



The Bracts and Flowers. The grasses form a natural 

 order which is one of the easiest to learn to recognize, but for 

 this very reason it is generally difficult to distinguish the several 

 species. 



The best characters for describing grasses are found in connec- 

 tion with the bracts, flowers and the ripened ovary. 



A great diversity of views have been entertained by leading 

 botanists in relation to the morphology of the flower and the 

 names to be given to each part. 



According to our best modern authorities, including Bentham, 

 Hooker, Gray, Sachs, Munro, and Doll, the three outer scales con- 

 stitute no part of the flower, but answer to bracts. 



Morphology of the Bracts and Flowers. The following is 

 a full abstract of an able essay on this subject, by the late Geo. 

 Bentham, and is taken from the Transactions of the Linnean 

 Society : 



The terminology adopted by botanists has been very unsettled 

 and repeatedly modified. The absence of all homology be- 

 tween the so-called sepals in grasses and those of perfect 

 flowers has been repeatedly demonstrated. Some years ago, when 

 preparing my Handbook of the British Flora, I purposed following 

 Kunth, but I was soon brought to a standstill by the anomaly of 

 the spikelet of Milium, being described as having two flowers 



Fig. 51. A plant of Poa pratensis, L. (June grass). At 1, a small plant, with 

 roots, root-stocks, leaves, culm and flowers ; e, part of a sheath of a leaf with a white 

 ligule, above which is part of a blade ; a, tpikelet, closed, containing four florets ; ft, 

 spikelet spread open, containing five florets, as seen when in flower : the lower scales 

 as seen in a and b, are the empty glumes, c, a floret, with, floral glume at the right. 

 palen at the left, including three stamens ; /, cross-section of the floral glume which 

 is 5-ribbed, and keeled ; d, a pistil with the ovary below bearing two short styles, each 

 terminated by a feathery stigma; at the base on each side is a lodicule. (Scnbner.) 



According fco Robert Brown, the two lower scales of a and ft are the glumce, and con- 

 stitute an involucre. They are the empty glumes or basal glumes of many authors; 

 palece of Dumortier ; teamen of Palisot de Beauvois. According to Robert Brown 

 and Jussieu, the two scales at c, are the paleoz, and represent the sepals ; glu'inettce of 

 Dumortier; straaulaot Palisot de Beauvois; periantJiium of authors. According to 

 R. Brown and Jussieu, the right hand scale in c is the loiver or miter palea, glumen 

 fertile of Germain de St. Pierre; flowering glume of Bentham, Hooker, Doll. 



According to R. Brown and Jussieu, the blunt scale at the left in c is the Interior 

 palea , poleola interior of Damortier ; zpathetta of D811. According to R. Brown and 

 Kunth, the small scales at d are the squamulce : lodieules of Bentham and others ; 

 nectaria of Scheber ; glumellce of some authors. By many, these scales were thought 

 to represent petals. 



