Pammel — Caryopsis and Endosperm of some Grasses. 205 



densely filled with protein grains. The starch cells with 

 rather thick walls. The starch grains are large and more 

 loosely arranged. This is a deviation from the type usually 

 found in the tribe Paniceae (PI. XIX. 1). 



PHALARIDEAE. 



Harz ^ has studied Phalaris canariensis, and P. arundinacea 

 as well as Anthoxanthum and Hierochloe. The brown pericarp 

 of Canary grass has rather thick-walled epidermal cells. The 

 underlying cells are thin- walled, and tangentially elongated. 

 The testa likewise consists of elongated thin-walled cells. 

 The cells of the aleurone layer are rather large, in a single 

 row. The starch cells are large, containing large compound 

 grains. 



Phalaris a7'un(Unacea , L. It is extremely diJEEcult to cut 

 good sections of Reed Canary grass. The brown pericarp is not 

 greatly developed. The epidermal cells are elongated tan- 

 gentially, thick-walled. The underlying layer of the pericarp 

 also consists of thick-walled cells. The walls of the testa are 

 thin and the layer is much compressed. The aleurone layer 

 consists of a single row of cells somewhat variable in size, 

 usuall}' as long as wide. The cells of the starch layer are 

 large, densely filled with large compound starch grains. The 

 individual elements are angular. The central part of each 

 separate grain is marked by a nucleus (PI. XVII. 9). 



AGROSTIDEAE. 



A number of species and genera of the tribe Agrostideae 

 have been studied by Harz,^ especially Calamagrostis, 

 Agrostis, Alopecurus, Phleum and /Stipa. 



Arisiida ramosissima, Engelm. In this Triple-awned 

 grass the pericarp is but slightly developed. The outer 

 portion consists of thick-walled rectangular cells. But 

 a single layer of cells of the testa is evident. They 



1 1. c. — P. canariensis, 1273. /. 1 70. 1-IV. — P. arundinacea, 1274. /. 1 70. 

 V-VIII. 



2 1. c. — Calamagrostis, 1264. — Agrostis, 1262. — Alopecurus, 1268. — 

 Phleum, 1270.— Utipa, 1282. — Ammophila, 1267. 



