Chap. II. HEEMINIUM MONORCHIS. 59 



accordance with the belief of Liniia-us, who grouped 

 them all together under the name of Ophrys insedifera. 

 Blr. Moo^o-rido-e further shows that in Italy 0. aranifera 

 flowers first, and 0. apifera last, the intermediate 

 forms at intermediate periods ; and according to Mr. 

 Oxenden, the same fact holds good to a certain extent 

 in Kent. The three forms which inhabit England do 

 not seem to blend into one another as in Italy, and I 

 am assured by Mr. Oxenden, who has closely attended 

 to these plants in their native homes, that 0. aranifera 

 and apifera always grow in distinct spots. The case 

 therefore is an interesting one, as here we have forms 

 which may be and generally have been ranked as true 

 species, but which in North Italy have not as yet been 

 fully differentiated. The case is all the more interest- 

 ing, as the intermediate forms can hardly be due to 

 the crossing of 0. aranifera with a/pifera ; this latter 

 species being regularly self-fertilised and apparently 

 never visited by insects. Whether we rank the several 

 forms of Ophrys as closely allied species or as mere 

 varieties of the same species, it is remarkable that 

 they should differ in a character of such physiological 

 importances as the flowers of some being plainly 

 adapted for self-fertilisation, whilst the flowers ol 

 others are strictly adapted for cross-fertilisation, being 

 utterly sterile if not visited by insects. 



Herminium ononorchis. — The Musk Orchis, which is 

 a rare British plant, is generally spoken of as having 

 naked glands or discs, but this is not strictly correct. 

 The disc is of unusual size, nearly equalling the mass 

 of pollen-grains : it is subtriangular, with one side pro- 

 tuberant, and somev.hat resembles a distorted helmet 

 in shape : it is formed of hard tissue with the base 

 hollowed out, and viscid ; the base resting on and 

 being covered by a narrow strip of membrane, which id 



