rs 
BOTANICAL GAZETTE 
SEPTEMBER, 18092. 
Flowers and insects. IX. 
CHARLES ROBERTSON. 
YDRANGEA ARBORESCENS L.*—The stems rise from one to 
Several feet high and bear flat-topped pound cymes measur- 
‘img seven to ten centimeters across. Each cyme is commonly 
Surrounded by a few large sterile flowers which render it much 
More conspicuous. These sterile flowers are remarkably per- 
Sistent, retaining their form throughout the winter, though 
they lose their color. 
_ The entire fertile flower with its pedicel is white. The 
Petals are small and soon fall. The stamens, which are com- 
Monly ten, with their large anthers, are the most conspicu- 
‘ous part of the flower. When dehiscent they far overtop the 
‘Stigmas. Nectar is secreted on the base of the styles, though 
" Pollen is the chief attraction. 
h: 
Ymenoptera—A pide : (1) Bombus separatus Cr. ¥, ¢. P-s 
(2) B. americanorum F. 2, c. p,; (3) Ceratina dupla Ss y 
and c. p.; (4) Heriades carinatum Cr. 9, c. p.; Andrenide: 
Augochlora_ labrosa Say 9, s. and c. p.; (6) Halictus 
‘Pectoralis Sm. 9, s. and c. p.; (7) H. similis Sm. 9 s. and c. 
a (8) H. truncatus Rob. (MS.) 9, s. and c. p.; (9) H. fascia- 
1) “As 2c. p.; (10) H. confusus Sm. Q, s. and c. p., ab.; 
- Stultus Cr. 9, s. and c. p., ab.; (12) Prosopis affinis 
a om & and f. p., ab.; Crabronide: (13) Crabro interruptus 
ty Ss. z 
ern So rere 
a i ife hi ts, No. II, Proc. 
Acad. Nat. Sci., Phil. — to the life reas of plan 
Vol. XVII.— No, 9, 
