BUTTERWORT TRIBE 233 



I. Verbena {Vervain) 



I. V. officinalis (Common Vervain). — The only British species. 

 A slender plant 1-2 feet liigh, with l)ut= few leaves, which are 

 roughish, 3-cleft, or simply cut. The flowers, whicli are very small, 

 are lilac, and grow in terminal, very slender spikes. Waste ground ; 

 common. — Fl. July, August. Perennial. 



Natural Order LXI 



LENTIBULARIACE^.— ButtiIrwort Tribe 



Calyx divided, not falling off ; corolla irregular, 2-lipped ; slamens 

 2, sometimes 4, 2 long and 2 short ; ovary i-celled ; style I, very 

 short ; stigma 2dii)ped, the lower lip smallest ; capsule i-celled, 

 2-valved, many-seeded. Herbaceous aquatic plants, bearing either 

 undivided leaves, which spring directly from the root, or compound 

 root-like leaves, with numerous small bladders or air-vessels. There 

 are but four genera in the Order, two of which contain British 

 examples — Butterwort (Pingiiicula), small plants with handsome 

 purple flowers and concave leaves, of a texture which resembles 

 greasy parchment; and Bladderwort (Ufrictdaria), submersed 

 plants with finely divided leaves,, bearing minute bladders and 

 yellow flowers, which rise above the surface of the water to open. 

 Both Butterwort and Bladderwort are carnivorous, in that small 

 insects become caught by sticking to the greasy leaves of the former, 

 and minute water insects, entering the bladders of Utricularia by 

 trap) doors, with which they are furnished, likewise become prisoners. 



" Pinguicula vulgaris (Common Butterwort) has the property of 

 giving consistence to milk, and of preventing its separating into 

 either whey or cream. Linnaeus says that the solid milk of the Lap- 

 landers is prepared by pouring it, warm from the cow, over a 

 strainer on which fresh leaves of Pinguicula have been laid. The 

 milk, after passing among them, is left for a day or two to stand, 

 until it begins to turn sour ; it throws up no cream, but becomes 

 compact and tenacious, and most delicious in taste. It is not 

 necessary that fresh leaves should be used after the milk is once 

 turned ; on the contrarj', a small portion of this solid milk will act 

 upon that which is fresh, in the manner of 37east " (Lindley). 



1. Pinguicula (Butterwort), — Calyx 2-lipped, upper lip 3-cleft, 

 lower 2-cleft ; corolla gaping, spurred. (Name from the Latin, 

 pinguis, fat, the leaves Iseing greasy to the touch.) 



2. Utricularia (Bladderwort). — Calyx of 2 equal sepals ; corolla 

 personate, spurred. (Name from the Latin, Utriculus, a little 

 bladder, from the little air-bladders which grow among the leaves.) 



