1817.] GENUS COLLINSIA. 189 



Fig. 11. Mcandrinalab?jrmt/iica: a^stvef^^tx^pm{kd^.nu 

 m^\s united, of the natural size; 6, profile view 

 of an animal, magnified. 



Fig. 12. Astreu dichotoma: a, expanded animal, seen in 

 profile; b, tlie same viewed from above, both 

 greatly magnified. 



Description of Collinsia, a new genus of plants* 

 By Thomas Nut tall. 



In the spring'of 1810, during the course of an extensive 

 journey into the north-western interior of the territories of 

 the United States, I first became acquainted with the very 

 singular and interesting plant which forms the subject of the 

 present memoir. The specimens which I then obtained on 

 the alluvial soils of the Alleghany and on the borders of lake 

 Erie were finally lost. On arriving at St. Louis, near the 

 confluence of the Missouri and Mississippi rivers^ I found 

 that Mr. John Bradbury, a botanist, had also detected this 

 plant about the same time, on the banks of the Missouri 

 and Mississippi, but I saw no specimen. In the spring 

 of last year (1816), having undertaken a tour to the wes- 

 tern states, I determined, if possible, again to collect this 

 neglected plant, but after a journey of more than a hun- 

 dred miles, tfor scarcely any other purpose, I arrived at 

 Pittsburgh disappointed of my object. On descending 

 the Ohio, however, nearly to Galiopohs, I at last recog- 

 nised it on the more open alluvions of the river, ^A'ithered 

 and nearly past affording seed, accompanied by the Hes- 

 peris pinnatifida ?Lnd tht mttrtsimg Fhalangiwn esculen- 

 tum: from these seeds I have been at last fortunate enough 



