252 NINETEENTH REPORT. 



Triglochin maritimum Lin. var. sexangulare Reiclienb. I.e. fig. 92. 

 Triglochin elatum Nutt. Gen. I, 237, 1818. 



Triglochin maritimum Lin. var. elatum (Nutt.) A. Gr. Man. 437, 

 1856. 

 There are two forms of the SjDike Grass ; one with ovoid fruit without 

 a neck at the apex and with rounded carpels ; the other has oblong fruit 

 contracted into a neck at the apex and the carpels liave depressed backs. 

 The former is typical of the species and the edges of the carpels are not 

 sharply acute; in the latter which is characteristic of the variety the 

 carpels are sharply acute or winged. Reichenbach's varietal name is 

 older by seven years than that of Gray and should be adopted. Both 

 the species and the variety were accredited to Michigan (Great Lakes 

 region) but all the Michigan material which has passed under my 

 observation is of the variety. The cross section of the fruit of the species 

 is circular in outline while that of the variety is strongly and regularly 

 angular with concave edges between the angles. Marl lake, No. 4292, 

 July 9, 1916. 



ALISMATACE^. 



Sagittaria latifolia Willd. 



In most of its forms this species is common throughout the state. At 

 Marl lake a form was found that had narrowly linear blades and lobes 

 which unquestionably is the forma gracilis (Ph.) Robinson. Not before 

 reported from the state. No. 4362, Aug. 13, 1916. 



GRAMINACE^. 



Zizania aquatica Lin. 



There are two species of Water Oats or Indian Rice in Michigan. One 

 is a tall, coarse plant with broad leaves and is the Z. palustris Lin. The 

 other is a slender, small plant with very narrow leaves and is the 

 Z. aquatica Lin. They are seldom found growing together but when 

 they are so found they are readily distinguished, and do not seem to 

 intergrade. Marl lake No. 4372, Aug. 13, 1916, and No. 2115 from 

 Huron River near Geddcs, Aug. 21, 1909, are Z. aquatica Lin. No. 1297, 

 August 12, 1892, from Belle Isle; No. 1297a, August 14, 1909, from 

 Grosse Isle; and No. 1297b, from Huron River near Geddes ; are Z. palus- 

 tris Lin. 



Spartina patens Var. juncea (Mx.) A. S. H. No. 4111, Sept. 23, 1915. 



An Atlantic salt-M'ater-marsli plant that has become established in the 

 salt marshes at Oakwood. 



