/ 



82 PETOH : 



the leaves are 20-26 cm. long, and 2 • 8-3 • 3 cm. broad, with the 

 tips barely incised. The peduncle is much longer than that of 

 S. Wightianum, and the flowers more scattered ; the whole 

 inflorescence on the herbarium specimen is 20 cm. long, with 

 scattered branches from the base upwards, but the one 

 figured is only 15 cm. long, unbranched, with flowers only near 

 the apex. In the inflorescence figured only two lips are 

 evident, and these are yellow ; a flower drawn separately has 

 also a yellow lip with four minute red dots at the tip. 



The herbarium specimens of S. longifolium were collected by 

 Thwaites in 1865 at Kitulgala. I have recently received 

 living plants of the same species from that locality and from 

 Bibile, collected by Mr. H. F. Tomalin, Conservator of 

 Forests. 



The first point which strikes one on seeing living examples 

 of these two species is the marked difference in habit. Sacco- 

 labium Wightiavium forms a tangled mass, its stems hanging 

 down and curving upwards at the extremity ; while 8. 

 longifolium produces erect stems up to 30 cm. high. 



The second point of difference is the length of the inflores- 

 cence. In S. Wightiaimm the inflorescence is short, not more 

 than 5 cm. high, and forms a compact head of flowers ; while 

 in 8. longifolium it is up to 25 cm. high, with scattered branches. 



The length of the leaf is variable, and on some plants of 8. 

 longifolium the leaves do not exceed 15 cm. in length. They 

 are, however, as a rule, broader than in 8. Wighiianum, and 

 the breadth diminishes slightly towards the tip. But the leaf 

 characters are scarcely sufficient to separate the two species. 



The flower of 8. longifolium, is usually larger than that of 

 S. Wightianum, and may attain a diameter of 18 mm. It is 

 more clearly yellow, not greenish-yellow, but the differences in 

 colour between the two species are slight. The barring and 

 spotting of the sepals, petals, and lip are the same in both, and 

 in both species the lip is at first white and subsequently 

 becomes yellow. The side lobes of the lip are hairy on the 

 inner surface, and there is a small vertical hairy plate or tooth 

 in the mouth of the sac, which is smaller than the correspond- 

 ing plate in 8. Wightianum. The base of the spur is yellow 

 from the first. 



