VOL. III.] Insects, on Tacca Blooms. ii 



o 



bloom; longifolia was just getting beyond its prime. Gilia spicata 

 was not found on this trip, although it was in bloom near by. 



Phacelia circiyiata, Frankliuii, sericea and Menziesii were all in 

 bloom though not all found by our party on that excursion. 

 Echinospermnin fioribundiim and Redowskii were in bloom, while 

 Omphalodes Howardi was in fruit. Krynitskia glomeraia was in 

 fine condition. Mertensia oblongifolia had passed into fruit, but 

 Sibirica was in prime condition. Lithospermmn pilosuvi and an- 

 oiistifoliiwi had gone to fruit. Collinsia parviflora was past its 

 prime. The Pentstemons in bloom were acuminaius, cristaius, coji- 

 fertus var. cceruleo-piirpureus , and one as yet unidentified. Syn- 

 thyris rubra had gone to seed. Castilleia mirieata 2S\A pallida were 

 sparingly found. Planiago eriopoda was plentiful on the plains. 

 Erwgo?iuni iimbellaiu7n was just coming into bloom, and Shepherdia 

 Canadensis going out of bloom. Betula occideiitalis, Alnus viridis, 

 Salix longifolia, flavescens, rosirata and Popiihis tremnloides lined 

 the brook sides. 



Cypripediuni parvijlorum, Iris Missoiiriensis, Sisyrinchium mu- 

 cronahun, Camassia esaclejita, Smilacina amplexicaulis and stellata, 

 Fritillaria atropiirpjtrea, Erythroiium grandiflonan var. minor, 

 Streptopus amp lexif alius, Prosartes trachycarpa, Zygadenus elegans 

 were the liliaceous flowers in bloom. Leucocrinum viontamwi and 

 Fritillaria piidica had long disappeared. 



Of Conifers we met Juniper communis, Pseudotsuga Dou^lasii, 

 Pinus fiexilis var. albicaulis, Pinus ponderosa var. scopulorum, and 

 Pinus contorta var. Murray ana. 



INSECTS FREQUENTING YUCCA BLOOMS. 



BY C. H. TYLER TOWNSEND. 



Any obsevations, however imperfect, relating to insects found fre- 

 quenting the flowers of the various species of Yucca, are of much 

 interest and. value, in view of the attention which is being given to 

 this subject by Dr. Riley, Prof Trelease. and others. 



It is believed by many persons now, since Dr. Riley first advanced 

 the idea some years ago, that certain species of Pronuba, a genus of 

 of small moths, are more or less indispensable to the fertilization of 

 the Yucca flowers. Moreover, the benefit between the moth and 

 the plant is believed to be mutual, inasmuch as the moth deposits 



