446 Trans. Acad. Sci. of St. Louis. 
(32) P. pygmaea Cr. ¢'9, s., ab.; Vespidae: (33) Polistes metricus Say, s.;, 
Eumenidae: (34) Eumenes tehtumais Say, s., freq.; (385) Odynerus walshia- 
nus Sauss., s.; (36) O. tigris Sauss., s.; (37)0. capra Sauss., s.; (38) O. fora- 
minatus Sauss., s.; (39) O. anormis Say, s.; Crabronidae: (40) Crabro 
scutellatus Say, s. 
Dipter na Se A (41) Stratiomyia discalis Lw., s.; Syrphidae: 
a Mahinda nitida Wd.; (43) Didea fasciata fuscipes Will.; (44) Xan- 
a emarginata Say (4 5) Mesograpta geminata Say; ( 46) Volucella 
ve cies F.; (47) Tiistitte dimidiatus Wd.; (48) E. latifrons Lw.; (49) E 
transversus Wd.; (50) Helophilus ae atee;3 (51) Mallota cimbiciformis 
Fll.; (52) Syritta pipiens L.— alls. or f. p.; Sarcophagidae: (53) pepe 
Spi; 8.5 ( nes Sarcophaga sp., 8.; Hisiton: (55) Cyrtoneura sp., 56) 
Lucilia sp., s.; (57) Lucilia caesar L., s.; ae (58-59) Caorenenits 
Spp.; mt ened (60) Camptoneura pita ii; 
Coleoptera — Buprestidae: (61) serine cate a Web., s.; Scarabaeidae: 
(62) Buphoria fulgida F., s.; Cerambycidae: (63) Molorchus bimaculatus 
Say, 8 
Lepido ptera — Nymphalidae: (64) Danais archippus F.; Lycaenidae: a 
hea pseudargiolus B.—L.; Papilionidae: (66) Papilio philenor L 
alls 
AMELANCHIER CANADENSIS Torr and Gr. — This is the ear- 
liest of the indigenous Rosaceae — blooming from April 1 to 
27. In my neighborhood the small trees grow on high creek 
banks and are fairly white with the numerous Rowara) which 
appear before the leaves. The flowers are crowded in short 
racemes terminating the branches. The oblong petals meas- 
ure 12 or more mm. in length and are so closely interwoven 
with the petals of neighboring flowers that the more incon- 
spicuous flower-stalks and calyces are concealed, and the out- 
lines of the individual flowers are lost in the white mass. 
Nectar is secreted by that portion of the receptacular tube 
which lies between the ovary and the bases of the filaments. 
When the flower opens, the five styles, with their receptive 
stigmas, are exposed above the inflected stamens, whose an- 
thers are still closed. The stamens straighten and turn out- 
wards in succession, the anthers discharging their pollen in 
the same order. Five innermost stamens remain strongly 
inflected, with their large closed anthers obstructing the 
mouth of the tube until all of the other anthers have become 
emptied. The flowers are abundantly visited, and until the 
anthers dehisce, there is full opportunity, in all favorable 
weather, for the stigmas to receive pollen from other flowers 
of the same or of distinct trees. If such pollination does not 
