THE GENUS 0PIIRY5 381 



ones forni a sort of screen on each side. Every detail suggests pro- 

 tection as the ultimate object in view. 



The function of the sepals in the Pseudo-petahe is quite different. 

 It is to attract the insects necessary for the fertilization of the flower. 

 They are signals of invitation to the desired guests — easily seen and 

 alluring. Hence they are spread as wide as possible to display their 

 beauty to the fullest extent, the upper one erect, the side ones at 

 right angles to the axis of the flower. Hence too their colour, 

 ranging from pure white through various shades of rose and pink to 

 deep magenta, and it mu!,t be admitted that they make a most 

 effective show, far surpassing in this respect the Eu-sepalse, which 

 have to depend on the lip alone to announce their presence. 



A possible objection may be raised on the ground that this arrange- 

 ment sejDarates O. wpifera from O. homhyliflora, and that these are 

 allied by the shape of the labellum and the turning up of the 

 appendix behind it, to such an extent that they are included by 

 Barla and also by Ascherson and Graebner in their section Apifer^e. 

 It must however be remembered that many authors, following Keichen- 

 bach's example, consider homhylijlora so unique as to form the 

 representative of a separate section. In spite of the resemblance 

 referred to above, homhyliflora comes much nearer to aranifera than 

 to apiferci. Not only does it differ from the latter in the essential 

 particulars of the form and function of its sepals, but also in many 

 other details. Of all European species of Oplirys it has the most 

 dull and inconspicuous flowers, very like aranifera in general effect 

 but smaller and still less striking in appearance, whilst apifera is 

 showy and attractive. It further resembles aranifera rather than 

 apifera in habit, in the shape and disposition of its leaves, the colour 

 of the lip, and its division into only three lobes (whereas apifera has 

 five) and in the very short obtuse beak of the column, in marked 

 contrast to the very long curved beak of apifera. In the presence 

 of one or more tubers in addition to those at the base of the stem, and 

 their growth at the apex of a long fleshy rootlet, it stands alone 

 amongst European species of Ophrys. 



A further objection may be raised that O. aranifera^ though 

 belonging to the Eu-sepalse, is also found with petaloid sepals, as 

 shown in plates 54, 55, of Barla's Iconoyraphie. But the plants 

 there figured are not O. aranifera at all. Those with coloured sepals 

 on plate 54 are O. aracJinitiformis, Avhich had not been differentiated 

 from O. aranifera in Barla's time, but which with further research is 

 becoming more and more recognised as a constant and effective 

 species, whilst plate 55 consists of hybrids. I have seen very many 

 specimens of aranifera in England, France, Switzerland, Italy, Sicily, 

 and Malta, but I have never seen one with coloured sepals. So far from 

 showing a tendency to vary in this direction, aranifera, in its hybrids 

 with species of the section Pseudo-petalie, not infrequently exerts so 

 strong an influence that it ov^ercomes the heritage of petaloid sepals 

 in the second parent, and the offspring reverts to the green sepals of 

 aranifera. So-called aranifera with colovu'cd sepals will be found on 

 investigation to be either arachnififormis or a hybrid. 



There is. fui-ther, another point of difference between the Eu-sepala; 



2a2 



