626 



THE NATURE BOOK 



are of a glaucous, sea-green colour, and 

 altogether it is a plant which is so distinct 

 from others that it should be at once 

 recognised. Like the Dwarf Plume 

 Thistle, this plant does not extend beyond 

 the central and southern portions of 

 England ; it is to be found in flower 

 from the end of June to September. 



BEE ORCHIS 



Never shall I forget finding the Bee 

 Orchis {Ophrys apijcra) for the first time. 

 It was in a dry field, just under one of 

 the chalk downs in the Isle of Wight, 

 growing in great abundance, together 

 with the Perfohate Yellow-wort — which 

 plant I also saw then for the first time. 

 The family of Orchids, all the world over, 

 produces many of the most interesting 

 plants that are known. Their peculiar 

 shapes, colouring and construction all 

 tend to make them noticeable. 



The stem of the Bee Orchis grows as 

 much as eighteen inches high in a good 

 locality, and bears a few oblong leaves 

 near the base, and a few rather large 

 flowers towards the summit, each one 

 with a leafy bract. The whole of the 

 flower bears a distinct resemblance to a 

 big bee on the wing, the " hp " being 

 of a rich veh'ety brown, very downy on 

 the sides, and marked by paler hnes and 

 spots ; the outer sepals are prominent 

 and pale pink or greenish white. The 

 mimicry of nearly all the Orchids appears 

 to have the especial object of attracting 

 certain insects and birds with a view to 

 securing the transference of the pollen 

 from one plant to another, but in the 

 case of the Bee Orchis this does not seem 

 to be the case. Self-fertihsation appears 

 to take place in almost every instance. 

 for the pollen is contained in pear-shaped 

 masses, which, at the proper time, droj) 

 out and hang directly over the stigma, 

 so that the slightest breath of air is 

 sufficient to bring them in contact. What , 

 then, can be the reason for this curious 

 mimicry ? One botanist has suggested 

 that this resemblance to the bee was to 

 prevent insects visiting the flowers, but 

 Darwin — who devoted a special book to 

 the various methods of orchids to secu:e 

 fertilisation— believed that the mimicry 

 served to secure an occasional cross. 

 Neither of these explanations is very 



satisfactory. It is hard to imagine that 

 the plant has taken such pains for, it 

 must be some hundreds of years, to 

 arrive at this stage, and has attained no 

 special object by doing so. Is it only a 

 freak of nature, and not an instance of 

 mimicry at all ? The name Ophrvs comes 

 from a Greek word signifying an eyebrow. 

 Phny states that a member of this genus 

 was used in ancient times to darken the 

 eyebrows. 



lady's tresses 



The Lady's Tresses {Spiranthes niitum- 

 nalis) is another representative of the 

 Orchid family to be found on the downs 

 and on dr}-, upland pastures. It flowers 

 somewhat late in the year, and should 

 be looked for in September and October. 

 Identification should not be difficult ; 

 the photograph shows well the peculiar 

 spiral arrangement of the blossoms on 

 the stem. The flowers are white and 

 fragrant, and at the base of each is a 

 leafy bract, which remains upright on one 

 side of the stem, while the flower diverges 

 horizontally to the other side. The broad 

 leaves grow in a tuft at the base, and the 

 flowering stems appear by the side ; up 

 the stem will be seen short, pointed leafy 

 scales. 



ROCK ROSE 



A fairly common plant, which is to be 

 found in summer and early autumn 

 growing in dry pastures, especially in 

 chalky and gravelly districts, is the 

 Rock Rose [Helianthemum Chanicrcistits). 

 It possesses somewhat woody stems, which 

 trail along the ground and send up erect 

 flowering branches ; the lower }:)ortions 

 of the stem are smooth, frequently hairy, 

 and of a reddish colour. The lea\'es grow 

 in pairs, but are somewhat irregular and 

 become smaller as they approach the 

 flowers ; they have i,hort footstalks, 

 and roll their edges backwards ; the 

 underneatli is gre}'. from a fine coating of 

 down. The bright yellow flowers, with 

 rather crumpled petals, are borne in a 

 loose raceme, the flower stalks being 

 slightly bent downwards both before and 

 after flowering ; there are five green 

 sepals, three of which are larger than 

 the other two — each of these has three ribs 

 and is nearly transparent, and concave in 

 shape ; the other two sepals are very 

 small. These flowers, beautiful as they 



