singular arrangement for shooting seeds was brought to my atten- 

 tion in the case of Gilia setosissima Gray. Wishing to collect 

 somewhat largely of the seeds of this neat little annual, I watched 

 more closely than usual the maturity of the capsules. In most of 

 the other species of this prevalent genus, there is a succession of 

 flowers and maturing capsules, which latter opening at the summit 

 discharge their seeds while the plant is still producing flowers, 

 thus rendering it difficult to secure a large quantity of seed with- 

 out including capsules not sufficiently mature. But in the case of 

 Gilia setosissima, all the capsules remain tightly closed till the 

 whole plant becomes dry and brittle. In then gathering seed by 

 picking each plant separately, I noticed the seed projected with 

 some force against my hand. On closer examination I found that 

 these capsules open from below upwards, and that the tension ac- 

 cumulated by the shrinking of the tissues in the process of drying 

 gives an elastic spring to the three separating valves when released 

 from their attachment at the base of the calyx, that throws the 

 contained seed from two to six feet. After making this discovery 



of the valv. s with the point of a knife, and see how far they would 

 shoot. The majority of the seeds were scattered within a radius 

 of two feet, while in the plumper capsules the shots took effect to 

 a distance of six feet or more. The three separated valves of the 

 capsules on account of their light chaffy texture were not thrown 

 as far as the seeds. 



A similar character, though less marked, was also exhibited in 

 certain species of caespitose Phlox, though in this latter case the 

 explosions observed occurred some time after the capsules were 

 detached from the calyx. The conclusion arrived at is that the 

 character of explosive capsules in this particular family is peculiar 

 to those that open at the base instead of the summit. 



In the succeeding paper I shall conclude this account of botani- 

 cal observations in Southern Utah by a notice of a short excursion 

 to the alpine district of Pine Mountain, and a more prolonged stay 

 in the vicinity of Cedar City, including a visit to the elevated sheep 

 pasture in the adjoining mountain range, — to be followed by an 

 appendix containing a full list of the plants collected, with de- 

 scriptions of the new or imperfectly known species. 



