46 Contributions to Western Botany. [zoe 



terus glomeratus the transition is complete. I have specimens 

 collected at Colorado Springs, Colo., whose seeds if taken from 

 the plants would be referred to Coloptcra Jonesii by the appearance 

 of the wings. This is No. 16 of my Colorado collection of 

 1878, now distributed widely. In Coloptej-a Jonesii the thickened 

 part of the wing is rather firm ("coiky "j and varies greatly in 

 thickness, and usually has a thin edge beyond the corky part. 

 In what must pass for Coloptera Parryi, from fifty miles south of 

 Lee's Ferry, Ariz., I find the wings much thinner than in 

 Cymopterus glomeratus, and most of them with scarcely a trace of 

 thickening, and in none of them would it be noticed by a casual 

 look, but the plant is no doubt a true Coloptera otherwise, the 

 more numerous oil tubes, the minute involucre, and the yellow 

 flowers being the only distinguishing characters. In Cynioptertis 

 globosns the wings are thickened at the apex as much as in any 

 Coloptera, but they are very spongy and soft. In Cymopterus 

 megacephalus the wings at the apex closely resemble Coloptera 

 Parryi in the variable thickening. The inconstant thickening of 

 the wings is well shown in Coloptera Jojiesii, where the dorsal 

 ones are as thin as paper throughout, or nearly as thick as the 

 lateral ones. At other times the dorsal wings are absent alto- 

 gether, or only a filiform ridge; the shape of the seed is various; 

 often it is very deeply concave, at other times it is scarcely 

 concave; the lateral wings vary much; at times they are con- 

 tracted around the deeply concave seed so as to form a cup like 

 the variet}^ eupulatum of Ec/miospermum Redowskii; at other 

 limes they are wide and flat. 



Another character relied upon by Coulter and Rose for 

 Coloptera is the absence of an involucre (which is also true of 

 Cymopterus glomeratus'). Unfortunately they overlooked this 

 involucre in ever}' case except C Parryi, and I doubt not that it 

 is found in that species also if plants fitting their description in 

 every other respect are rightly referred there. In C Newberryi 

 and C Jonesii I have seldom found it absent, but when it is 

 reduced to a vestige as is often the case it would readily pass for 

 a fold in the top of the peduncle and would lead one to think 

 that the top of the peduncle was fleshy in the green plant, but 

 that is never the case. Under the microscope this is at once 



