158 BOTANICAL GAZETTE [aucust 
numerous greenish flowers which appear with the leaves. The 
stamens are exserted so that the pollen may be eaten by Syr- 
phide or collected by Andrenidz, but the style is short and 
included. The calyx tube is about 2™ deep and 17” wide. 
Consequently the nectar, which is secreted by a disk lining the 
tube, is readily accessible to small, short-tongued insects. From _ 
their structure and blooming time, April 23d to May toth, the 
flowers seem to be specially adapted to Andrenide, but they are 
also visited less abundantly and less efficiently by flies. Onthe 
Ist and 2d of May I captured the following visitors : 
HYMENOPTERA—A fide : (1) Apis mellifica L. %, s., one ; (2) Bombus ame 
ricanorum F. 9, s.; (3) Ceratina dupla Say 4, s.; (4) Nomada maculata Cr. % 
8.; Andrenide : (5) Halictus foxii Rob. @, s. and c. p., freq.; (6) H. arcuatus 
Rob. 9, s. and c. p-; (7) H. forbesii Rob. 9, s. and c. p.; (8) H. lerouxii Lep. % 
s. and c. p.; (9) H. fasciatus Nyl. 9, s. and c. p., ab.; (10) H. pilosus Sear 
s. and c. p., freq.; (11) H. confusus Sm., 9, s. and c. p., freq.; (12) H. prume 
sus Rob. 9, s.; (13) H. illinoensis Rob. 9, s.; (14) H. zephyrus Sm. 2, s, and ¢ 
wegra Wik.; 
rs cimbicis Twns.; Muscide - (47-48) Lucilia spp.; (49) L- ei = 
cordyluride : (50) Scatophaga squalida Mg.; Amthomyide@: (51) 
acra WIk.; (52) P, fusciceps Zett.—all s. or f. p. : 
On the literature of Rhamnus see : 
(1) Darwin, on the two forms, or dimorphic condition, in the ee 
Primula, and on their remarkable sexual relations; Journ inn 
" neilung bed 
9:95. 1862—R. lanceolata, (2) Hildebrand, Geschlechtsverthel seus 
Pflanzen 9: 40, 1867—R. cathartica, lanceolata. (3) Miller, Bet 
