332 THE .TOriiyVL OF DOT ANT 



and Pseudo-petaliB. All tlie latter have an appendix atHhe apex 

 of the lip, and in several species, e.g., arachnites^ scolopax and 

 fenthredinifera, it is large and rather conspicuous. In the former 

 there is no appendix, except in the ease of O. bombijlijlora, which has 

 a rather thick triangular one, turned up, like apifera, at the back of 

 the lip. This is the onh' instance of a really developed appendix in 

 that section. Rarely aranifera has a very short rudimentary appendix, 

 but it is at least doubtful whether this is not due to hybrid inlluenee. 



It is difficult to see why an appendix should always be found in 

 conjunction with petaloid sepals, but such is the case. It is still 

 more difficult to understand why it should occur in homhijlrfiora. 

 The use of this organ to the plant is not easy to explain. It attains 

 its greatest development in those species with the largest and most 

 conspicuous flowers. It is usually stiif and rigid, and turned up in 

 front of the lip. Possibly it serves to stiffen the lip, to prevent it 

 from bendins: under the weisrht of an insect, and to srive a more solid 

 foot-hold to visitors. This, however, does not explain its presence in 

 apifera and homht/lijlora, in Avhich it is turned up at the back of the 

 labellum, where its use appears somewhat doubtful and obscure. 



It will I think be admitted that the above arrangement divides 

 the genus Ophrys into two eminently natural sections, easily distin- 

 guishable without reservations or exceptions, and with definite and 

 clear morphological and functional points of difference. 



The two sections indicated abov^e may be conveniently divided 

 into the following sub-sections : — 



A. EU-SEPAL^. 



I. ConvexilahelJce. 



Lip very convex, edges strongly revolute, appendix nil 

 (except in O. homhi/lijlora) or (very rarely) rudimentary. 

 O. aranifera, atrata, litigiosa, Tomassinii, homhylijiora. 



II. PlanilabeU'cB. 



Lip nearly flat, only slightly convex, appendix nil. 

 O.fnsca^ hitea^ paUida, speculum, muscifera. 



B. PSEL'DO-PETAL.E. 



I. lietroverscB. 



All lobes of lip revolute. Appendix turned up behind 

 the labellum. 

 O, apifera. 

 IL Porrecfce. 



Side lobes only of labellum revolute. Appendix turned 

 up in front of labellum. 



O. arachnites, scolopacc, cornuta. tenth red inif era, Ber- 

 totonii. 



III. Iludimentari(P. 



A])j)endix short, rudimentary. 

 O. exaJtata, arachnitiformis. 



