IOWA ACADEMY OF SCIENCES. 79 



Herbaceous plants not affected on November 4: Marruhlnm inJgnre, Diauthus 

 chinensis, Dipsaciis si/lrestrifi, Ce)itnurea ci/nnus (slightly), Cahndula ofjitiiialis, 

 Eschschohzin cnlifoniica (slightly), Tanacetnm rnlf/are, Triosteum perfollatum. 



None of the perennial grasses were aifected by frost up to November 4th. This 

 was also true of some of the annuals — Fhleum prnleuse, lironius inennis, D. bre- 

 riaristatus, D((ct!/lis (fhineratn, Afjr<-pi/ntm repens, A. glaucum, Agrostis alba, 

 Var. nilijaris, Chri/sopogoii nutans, Andropogon fiircatns. A, scoporins {the leaves 

 of these last three are turning brown); Spartina cgnosiiroides (yellow), Poa pra- 

 iensis and A vena saiiva. * 



Trees with green leaves on NovtMnber 4th: IJgustruin vnlgare, Eleagniis an- 

 gii.ilifoliaiiiome affected), Fntnns (Amggdalus) persicn, P. simoni,Quer cus robur, 

 Acer saccharinnni (a few trees), Quercus rubra (few), Q. macrocarpa (few), Sgr- 

 ingii vulgaris, S. persica (some few yellow leaves). 



The following notes on the flowering of a few plants may be of interest: 



October 27th: Scabio^n atropurpurea, Cidendnla officinalis, Melilotus officina- 

 lis, Leonurus cariliaca, Phlox drumninnlii, Trifolium pratense (sheltered place), 

 CoVinsia bicohr. ^ 



October 23d: Reseda odoratn, Erodium cicutarium, Marrubium vulgare, Po- 

 tentilla norvegica, Sonchus asper. Cassia marglandica, Erigeron annuum. Chrys- 

 anthemum coronarium, Lnthgrus odoratus, Nepeta cataria, Solidago canadensis, 

 Argcmone mexicana, Marutn cotula, Crgptotcenia canadensis, Polanisia graveo- 

 lens, Borrago officinalis, Saponaria officinalis. 



October 21st: Helianthus debilis, Gossypiuni hf)b icum, Ricinus communis, 

 Ipomtea purpurea, Salvia pratensls. 



NOTES ON THE POLLIXATION OF CUCURBllS. 



.\B3TRACT BY L. If. PAMMEL. 



Little attention has been given to a study of the pollination of cucurbits. The 

 European Brgonia dioica was studied by Hermann Miiller and Mr. T. C.Gentry 

 has studied Cucurbita ovifera and C ))<>po, but his account is quite inaccurate in 

 some important particulars. Mr. Gentry assumes that they are pollinated by the 

 wind. Insects, especially Ilgmenoptera, are the importantpollinators. Cohoptera, 

 especially Diabrotica vittata, D. longicornis, D. punctata, are frequently found in 

 flowers and incidentally carry the pollen. Some of the Syrphus flies also assist in 

 the pollination of Citrullus vulgaris. Nectar is secreted in considerable quantity 

 especially by the flowers of Cucurbita pcpo and C. maxima. So large was the 

 amount of nectar in some of the covered flowers of C. maxima that a halt spoonful 

 might have been collected. The odor of the flowers of C. maxima is quite pleasant 

 and agreeable. Concerning the sexes, Cucurbita maxima and C. pepo and Cu- 

 cumis sativus are monoecious. In Cucumis melo some varieties have perfect 

 flowers, e, g., they are polygamo-moncecious. Some varieties of Citrullus vulgaris 

 also are polygamo-moniecious. Before 12 m. seems to be the proper time for polli- 

 nation in Cucurbita pepo and C. maxima, while Citrullus vulgaris may be polli 

 nated in the afternoon. 



