OPHRYDE^—SERAPIADIN^— ORCHIS 175 



green, with six scarcely raised longitudinal ridges. Sepals ovate, obtuse, keeled, 

 5 -nerved, dark purplish or brownish red outside, greenish within, conniving with 

 petals to form a helmet. Petals small, of paler colour, shorter and narrower than 

 sepals, linear-spatulate, obtuse, i -nerved, apex sometimes notched or slightly toothed. 

 Lip slightly longer than sepals, directed forwards and downwards, 5-lobed, some- 

 what concave, with a groove at the base leading into the spur, white (rarely tinged 

 with rose) with a few irregular bright crimson spots; side-lobes divergent, rather 

 broad, oblong, rounded or squarish at apex, often crenate; mid-lobe longer and often 

 broader, widening downwards, and ending in two short more or less divergent 

 crenulate lobules, sometimes with a tooth between. Spur very short (±2 mm.), 

 conical, rounded at apex, compressed from back to front, directed downwards and 

 forwards. Throat of flower shaped like a key-hole. Column very short, whitish. 

 Anther ovate, pale yellow, cells contiguous, separated by a fold at base. Pollinia 

 very short, pale lemon-yellow, caudicles short, brighter yellow. Stigma partly con- 

 cealed by pouch of rostellum. Seed-capsule cylindrical with three obtuse ridges, 

 about 10 mm. long. Seeds oblong, slightly attenuated above. Cells of transparent 

 testa transversely striate. 



Smith' says that 0. ustulata imitates the delicious scent of heliotrope. 



The smallest flowered species of Orchis in Europe. The dark brownish red buds 

 give the top of the spike a charred appearance, whence the name Burnt Orchid. The 

 pure white lip contrasts well with the dark-coloured helmet, in which respect it 

 resembles in miniature 0. purpurea. It varies very little. On the Continent in favour- 

 able conditions the spike becomes long and cylindrical, and the plant is much taller 

 than in England, where it is usually dwarf. The lip is sometimes faintly flushed with 

 rose, and white-flowered forms have, though rarely, been found. A curious peloric 

 form, with the spurless lip exactly like the petals, was gathered by us at Aix-les-Bains, 

 the sepals and petals greenish with a narrow reddish edge, like Aceras anthropophora — 

 suggesting a reversion to a primitive type in which the lip had not yet been diifer- 

 entiated from the petals. A white variety was found near Chiswell, Berks. ^ 



Webster3 says that both pollinia are attached to a common gland, as in the Lizard 

 Orchid. Colonel G. H. Evans, F.L.S., a skilled microscopist, dissected a number of 

 flowers from difl"erent spikes with me on May 1 7th, 1929. We found that each pollinium 

 was attached to a separate disc, and that in situ, in the pouch of the rostellum, the 

 two discs are separated by an appreciable space. Webster's specimen was not normal, 

 but a case of accidental adherence of the two discs, which also occurs not infrequently 

 in Aceras. If both pollinia were attached to the same disc, O. ustulata would not 

 belong to the genus Orchis, as now understood, but to Himantoglossum. 



• Cat. Plants S. Kent (1829). 2 English Flora (1828). 



3 Brit. Orch. ed. i, p. 15 (1886). 



