varrurj] THE MECHANISMS OF FLOWERS. 329 
_L.; (85) L. livida, F., both f.p.; (e) Coccinellide : (86) Exochomus auritus, 
Scriba, ab. ; (d) Chrysomelide : (87) Cryptocephalus sericeus, L., feeding on 
_ the tissues of the flower. Forty-three additional visitors (including fifteen 
_ beetles) are enumerated in No. 590, 11. See also No. 609. 
Hq 227. ANTHEMIS ARVENSIS, L.—The structure of the flower is 
similar to that of Chrysanthemum lewcanthemum and Matricaria 
~Chamomiilla ; in regard to conspicuousness and amount of insect- 
visits it stands between the other two. Each capitulum forms 
_ a white circle 21 to 27 mm. in diameter, with a central yellow 
disk 5 to 7 mm. in diameter. Since the plant does not possess 
the strong odour of MZ. Chamomvilla it is visited by numerous bees. 
| Visitors : A. Hymenoptera—(a) Apide : (1) Apis mellifica, L.$,s.; (2) An- 
drena Schrankella, Nyl. 9, ¢.p. and s.; (3) A. nigrownea, K. 9, c¢.p. and s. ; 
_ (4) A. fulvierus, K. 9, cp. and s.; (5) A. nana, K. ?,s.; (6) A. minutula, 
_K. ¢; (7) Halictus lucidulus, Schenck, 2; (8) H. nitidiusculus, K. ? ; (9) 
_ Colletes Davieseana, K. 9 g, cp. and s, ab.; (b) Sphegide: (10) Cerceris 
' variabilis, Schrk. ¢; (11) Crabro cribrarius, L., Dib. 2; (12) Cr. alatus, Pz. 
623 (¢) Tenthredinide : (13) Tenthredo notha, Kl. B. Diptera—(a) Stra- 
_ tiomyide : (14) Nemotelus pantherinus, L., very ab. ; (b) Syrphide-: (15) Eri- 
’ stalis arbustorum, L.; (16) E. nemorum, L.; (17) E. tenax, L.; (18) E 
sepulcralis, L., all four fp., ab. ; (19) Syritta pipiens, L.; (c) Muscide : (20) 
Echinomyia Gecnelata F.; (21) Scatophaga stercoraria, L. ; (22) Sc. mae 
f., all three fp. C. Coleoptera—(a) Elateridew : (23) Athous niger, L. ; (d) 
reulionide : (24) Bruchus sp.; (¢) Cerambycide : (25) Leptura livida, L. 
228. ANTHEMIS TINCTORIA, L. (Thuringia, July, 1868 and 
| 1870) :— 
Visitors ; A. Hymenoptera—(a) Apid@: (1) Colletes marginata, L. ¢, s. ; 
' (2) Halictus maculatus, Sm. 9, ¢.p.; (3) Heriades truncorum, L. ?,s. and 
| e.p.; (b) Ichneumonide: (4) Various sp. B. Diptera—(a) Syrphide: (5) 
 Eristalis arbustorum, L. ; (6) Syritta pipiens, L.; (7) Melithreptus teeniatus, 
~ Mgn., all three fip.; (b) Conopidw: (8) Myopa sp., s.; (c) Muscide: (9) 
_ Gymnosoma rotundata, L. ; (10) Ulidia erythrophthalma, Mgn., in hundreds. 
| D. Coleoptera—(a) Elateride ; (11) Agriotes gallicus, Lap. ; (b) Mordellide : 
| (12) Mordella fasciata, F, Delpino mentions as a visitor of this plant Lomatia 
_ Beelzebub, F. (Diptera, Bombylide). (No. 178, p. 121.) The flowers are 
‘described and additional visitors are enumerated in No. 590. 
__—- 229. CHRYSANTHEMUM LEUCANTHEMUM, L. (Fig. 112, 6—8). 
Four to five hundred florets, in which the corolla is scarcely 3 mm. 
_ long, unite to form a yellow disk 12 to 15 mm. in diameter; 
at its edge are twenty to twenty-five florets with abortive 
stamens, each of which has a white external lobe, 14 to 18 mm. 
“cng, 3 to 6 mm. broad, so that the yellow disk is surrounded by a 
white border as broad as or broader than itself, and the whole attrac- 
| tive surface now has a diameter of 40 or more millimetres, In the 
*, alll 
