472 THE FERTILISATION OF FLOWERS. [PART 111. 
separate, the anthers are already withered and bent downwards. 
The wide space between the anthers and stigmas seems sufficient 
to prevent self-fertilisation even without the help of proterandry. 
In spite of the small, inconspicuous flowers, insect~-visitors are 
numerous and varied. 
While in Salvia the abortion of two stamens may be explained 
by the development of the lever-mechanism which they would 
have interfered with, in Lycopus their disappearance is due simply 
to the small size of the flower; and though only two are present, 
the small size of the flower causes every insect to come in contact 
with them. The same explanation holds good for Veronica, whose 
Fic. 160.—Lycopus europeeus, L. 
1.—F lower, in first (male) stage, from below. 
_ 2,—Ditto, in second (female) stage, from the side. This figure should be horizontal. 
3.—Ditto, in first stage, after removal of the under lip, from below. 
a, abortive stamens; n, nectary; a’, perfect anthers, before dehiscence; a, ditto, dehiscing ; 
a3, ditto, withered ; st’, stigma, still immature; st, ditto, ripe. 
flowers are the smallest among Scrophularinez as those of Lycopus 
are among Labiates. 
Visitors : A. Hymenoptera—Vespide : (1) Polistes gallica, L., and var. 
diadema, s., freq. (Thur.). B. Diptera—(a) Syrphide: (2) Melithreptus 
scriptus, L., s. and f.p. ; (3) Syritta pipiens, L., very ab., s. and f.p. ; (6) Mu- 
scide : (4) Lucilia silvarum, Mgn. ; (5) L. cornicina, F., both s., freq. ; (6) 
Sarcophaga albiceps, Mgn., ab., s. ; (7) Pollenia Vespillo, F.,s, Also many small 
gnats 14 mm. long. C. Hemiptera—(8) Some undetermined species of bugs. 
D. Lepidoptera—(9) Adela sp.,s. E, Thysanoptera—(10) Thrips, very ab, 
340. THymus SERPYLLUM (L.), Fr—Our two species of Thymus 
have, like Nepeta, stocks of two kinds, one with large herma- 
phrodite, the other with small pistillate flowers. 
Hildebrand (351) has sought to ascribe the origin of the small- 
flowered female plants to the proterandrous condition of the 
