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far found them only upon the leaves, the juice of which serves them as 

 food. The first of these is a small brown Capsid known as HaUicotoma 

 valida; the second, a curious Horaopterous insect, Ticida cinf/tdata, of 

 a brownish color, banded with white; the third and last is a Ooccid, 

 Fseudococcm yiicae, having the general aspect of the common mealy- 

 bug of our hothouses. 



Certain other kinds of insects, notably locusts, are occasionally found 

 among the leaves of this Yucca, but as they have not been observed to 

 feed upon this plant, their presence upon it appears to have been purely 

 accidental, and not for the purpose of obtaining food. 



The following is a list of the insects that 1 have observed within or 

 among the flowers of Yucca icMpplei : 



Coleoptera— Contuiued. 



Hymeuoptera : Hippodamia convergens. 



Fluti/Iabus .sj>. f Anthonarus agcirensis. 



Lepiclopterar! Carpophilus palUpennia. 



Lapliygma fruf/iperda. Acmceops faUa. 



Pronuha maciilaia. Diahrotica'soror. 



Prodoxns marghiattis, Diahrotica tiivittala. 



Prodoxus wnescens. Tlemiptera: 



Diptera : Ai)hh sp. ? 



Genus? Species f Family Geomy- ThnnmotetUx scuteUaia. 



zid*. Neuropteia: 



Coleoptera : Chrysopa sp. ? 



Ah'ochara up. ? 



Of these, the Laphygma was i)resent in three examples, but only at 

 night, and may have been attracted by the light from my lantern, since 

 they did not attempt to feed upon the flowers. Diahrotica soror was 

 observed to feed upon the pollen- masses as well as upon the perianth. 

 The Aphids were congregated upon the outside of the flowers. I did 

 not observe a single butterfly or wild bee of any kind visit these 

 flowers, although all of these insects were quite abundant in the vicinity 

 where these observations were made. And the same observation also 

 applies to humming-birds. Pronnha macnlata and the two species of 

 Prodoxus were present during the month of June and a portion of May 

 and July ; but none were observed after the 24th of July. The Prodoxus 

 moths usually rested upon the inside of the perianth, but the favorite 

 position of the Pronuha was resting upon the side of the ovary, her 

 head turned toward but not reaching the stigma. 



In 1892, at the request of Dr. Riley, I paid particular attention to the 

 pollination of this Yucca and the actions of Pronuha maculata. After 

 rei)eated watchiugs, both during the daytime and at night by the aid 

 of a lantern, I was fortunate enough to witness the process of egg-depos- 

 iting and pollinating. This was on the 12th of June of the present year. 

 The sun was only about forty minutes high, but was shining brightly, 

 and a cool breeze was blowing at the time. Tlie Yucca plant was about 

 eight feet high, and the flowers in the lower three-fifths of the panicle 



