LAB I AT AE 
439 
Ovary on a nectariferous disc (often developed on anterior side only), 
of (2) cpls. placed antero-posteriorly. Early in its development a 
constriction appears in the ovary in the antero-posterior line, dividing 
each cpl. into 2 loculi, so that the ovary becomes 4-loc. as it matures. 
Each of the 4 portions is nearly independent of the rest, and the style 
springs between them from the base of the ovary (i.e. is gynobasic); 
stigma 2-lobed. Placentae axile, each with 1 basal erect anatropous 
ovule with ventral raphe. The fruit is usually a group of 4 achenes or 
nutlets , each containing one seed ; sometimes it is a drupe. Seed with 
no endosperm or very little ; the radicle of the embryo points down- 
wards (cf. Boraginaceae). 
The firs, of L. belong in general to the classes H. and F. (pp. 92, 
91). The 2 -lipped corolla ensures that the visiting insect shall take a 
definite position in regard to the anthers and stigma whilst probing for 
the honey at the base of the fir. The lower lip acts as a flag to 
attract insects, and also as a landing-place, whilst the upper lip 
shelters the essential organs, which are usually placed so as to touch 
the insect’s back. The length of the corolla-tube varies very much, and 
with it the kind of visitors. Most Brit. sp. are bee firs., the long-tubed 
red firs, of Monarda &c. are butterfly firs., and a few sp. of Salvia &c. 
are humming-bird firs. (p. 99). The pollination-mechanism is usually 
simple ; in Lamium, &c. the fir. is homogamous, the stigma merely 
projecting beyond the anthers so as to be touched first, but usually 
the fir. is dichogamous (protandrous), often with movements of the 
essential organs, e.g. in Teucrium, &c. The lever-mechanism of 
Salvia is almost unique. Thymus, Origanum, and their allies, have 
nearly regular firs, visited by a more miscellaneous selection of insects. 
In many L., especially § VI., interesting distributions of sex appear, 
especially gynodioecism (p. 68). 
A few L. disperse their fruits by aid of the persistent bladdery 
calyx, which acts as a sail; a few have hooks formed from the calyx- 
teeth. The stalks are very often hygroscopic and move in such a 
way as to favour the dispersal of the fruits in wet weather (see Miss 
Pertz in Nat. Science , Oct. 1894). 
The L. are useful on account of the volatile oils which they con- 
tain ; many, e.g . Thymus, Ocimum, Origanum, Salvia, &c., are used 
as condiments. Oils and perfumes are obtained by distillation from 
Rosmarinus, Pogostemon, Lavandula, &c. Food-products are ob- 
tained from Stachys sp. 
Classification and chief genera (after Briquet, from whose account 
much of the above is condensed) : the L. are closely allied to Verbe- 
naceae ; from Boraginaceae the position of the radicle sharply separates 
them, whilst the similarity to Scrophulariaceae, &c. is largely in minor 
characters. 
A. Style not gynobasic. Nutlets with lateral-ventral attachment and 
usually large surface of contact (often > \ as high as ovary). 
