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HARDWICKE'S SCIENCE-GOSSIP. 



THE COMMON ORCHIS {ORCHIS 

 MASCULA). 



Its Inflorescence. 



By Edward Malan, M.A. 



{Continued from page 57.) 



NOW look at the next illustration of a single flower 

 (fig. 52). It is a miracle of design : compli- 

 cated certainly, but soon explained. The outer floral 

 envelope is composed of three pieces, the same 

 colour as the petals, and constitutes the calyx 

 (A, A, A,) which arrangement is called ternary. 

 The inner floral envelope, also of three pieces, is the 

 corolla, the lower one being the labellum (B, B, B). 

 This labellum is produced into the nectary (C), which 

 passes on one side of the twisted ovary (D). From 

 the base of the ovary a bract (E), forming a careful 

 protection for the bud, arises. Inside this bract the 

 bud reposes before it opens, with the nectary laid flat 

 against the stalk, so that when the flower first 

 appears it is topsy-turvy. The whole spike is en- 



and how is the flower of the common orchis fertilised ? 

 for self-fertilisation is out of the question. In 1840 

 the secret was not known, but it was supposed by 

 Dr. Lindley and others, that the pollen-grains passed 

 down into the ovules by means of the tissues, and it 

 was not until 1862, that the late Charles Darwin, 

 after years of laborious study, arrived at the truth. 

 His description of the performance, which he says 

 will not be endured by the general reader, leads to 

 absorbing admiration of plant and man. He says 

 (" Fertilization of Orchids," 2nd ed. p. 11) suppos- 

 ing a bee alights on the labellum, which forms a con- 

 venient landing-place, and thrusts its head into the 

 little yawning throat of the flower, so as to reach the 

 honey (propolis ?) in the papillae at the base of the 

 nectary : it is scarcely possible, owing to the shape 

 of the flower and its nicely-adjusted balance, not to 

 touch the rostellum. Directly the rostellum is touched, 

 a viscid drop exudes which sets hard and fast like 

 cement, and when the bee withdraws its head, apolli- 

 nium is firmly attached. Then another flower is 

 I visited, and behold ! instead of the pollinium remain- 



Fig 52. — a a a, sepals, same colour as petals ; b b b, petals, light pink, with rostellum and anthers at g and h ; c, labellum, with 

 nectary at n ; d, ovary, with nectary at n, labellum at c, and rictus at R ; e, bract ; f, fauces, with anthers showing. 



closed in a spathc, which keeps it safe from frost and 

 rain. The apparatus for perfecting a vast supply of 

 seed is the next thing to notice. In the gape of the 

 flower [rictus), and immediately between the helmet 

 and labellum, the conformation of the flower presents 

 the appearance of a throat. Protruding into the 

 throat from above, a fleshy process is seen, called the 

 rostellum (G), strangely resembling the human uvula. 

 This contains the pollinia, two in number, or large 

 waxy club-shaped masses of pollen, not yellow and 

 powdery as in the buttercup and other common 

 flowers, but free and bottle-green, connected by means 

 of tiny elastic threads, and supported by a long fila- 

 ment, with a minute viscid disc at the end. These 

 are the anthers, fitting into the anther-cells, from 

 which as the anther-cells are merely folded longitu- 

 dinally, they can easily be removed (A). The sta- 

 mens and style are consolidated into one column, and 

 the stigma is below and behind the rostellum. An 

 enlarged illustration will make this most intricate 

 plan clearer. 

 Now how is all this costly apparatus employed, 



ing erect, in thirty seconds the viscid disc has dried, 

 causing thereby the pollinium to sweep through an arc 

 of nearly 90 in the direction of the apex of the pro- 

 boscis, so that it exactly touches the stigma. For a 

 fuller account, the reader is recommended Darwin's 

 book. 



In hopes of witnessing this exceedingly curious 

 operation, I placed, on April 23rd, 1881, some blue- 

 bells, cowslips, and orchises out on the lawn, where 

 crowds of bees were busy in beds of Egyptian cress, 

 and pencil and paper were provided to check off 

 arrivals. The result is too long to give here, but 

 hardly had I settled down, when visitors began to 

 arrive, and during an hour and a half, no less than 

 twenty- eight bees, bumble and hive, approached the 

 plants. Sir John Lubbock would be gratified to 

 know that the bluebells only were visited. I inves- 

 tigated the pollen of the bluebell, cress, and cowslip, 

 under the microscope, and found that of the cress 

 and bluebell nearly homogeneous, and I was struck 

 by the wisdom of giving bees long-focussed eyesight, 

 which gains a variety of colouring for flowers, and 



