OrCHI DALES.] 



ORG HID ACE a:. 



179 



dicles, which are either bent down upon the masses themselves, or serve to hold them 

 together, without, however, forming any organised union with the stigma ; while the 

 remainder (Vaudese) have a caudiele, which adheres firndy to a gland found on the 

 upper margin of the stigma, and separating freely from that organ. The genera with 

 powdery, granular, or sectile pollen cannot be classified so conveniently by modifications 

 of that part, but are readily divided into 3 natural tribes by peculiarities in the anther. 

 In some (Ophrese) the anther is erect, not hinged to the column but continuous with it, 

 and stands above the stigma, the pollen masses having their points directed to the base 

 of the lobes of the anther ; in others (Arethusese) the anther is hmged to the column, 

 upon the end of wliich it is placed transversely like a lid ; and in others (Neotteee) it 

 is also hinged to the column, but is stationed at its back so as to be nearly parallel 

 with the stigmatic surface. If to this we add that Cypripedese have two anthers, while 

 all the others have one only, we find the Order divided into seven tribes, of which the 

 following is a tabular view\ 



B. Pollen powdery, (jranular, or sectile. 



a. Anther terminal, erect IV. Ophrece. 



b. Anther terminal, opercular Y . Arethusece . 



c. Anther dorsal VI. Neottece. 



VII. Cypripedea. 



I. Anther one only. 



A. Pollen masses uxixy. 



a. No caudiele or separable stigmatic gland 



I. Malaxece. 



b. A distinct caudiele, but no separable stigma- 

 tic gland II. Epidendre(e. II. Anthers two 



c. A distinct caudiele, united to a stigmatic 

 gland III. Vandece. 



Among many other remarkable peculiarities the irritability of the labellum must not 



be passed over in silence. This is extremely striking in various species of Pterostylis, in 



the genus Megaclinium, and in 

 many Bolbophylls, especially 

 barbigerum and Careyanum. 

 But some of the Sw-an River 

 species are still more sin- 

 gular. In Caleana nigrita, 

 Mr. Drummond describes the 

 structure to the following 

 effect. The column is a boat- 

 shaped box, resembling a 

 lower lip ; the labellum forms 

 a lid that exactly fits it, and 

 is hinged on a claw which 

 reaches the middle of the 

 2 column ; when the flower 

 open«, it (the labellum) turns 

 romid w^ithin the column, and 

 falls back, so that, the flower 

 being inverted, it stands fairly 

 Fig. CXXIII. over the latter. The moment 



a small insect touches its point, the labellum makes a sudden revolution, brings the point 



to the bottom of the column, passing the anther in its way, and thus makes prisoner 



any insect which the box will hold. When it 



catches an insect it remains shut while its prey 



continues to move about ; but if no capture is made 



the lid soon recovers its position. Another plant, 



Draksea elastica, has a single flower placed at the 



end of a .slender smooth erect scape, from twelve 



to eighteen inches high, and its labellum, which is 



hammer-headed, and placed on a long arm with a 



moveable elbow-joint in the middle, is stated by Mr. 



Drummond to resemble an insect suspended in the 



air, and moving with every breeze. Another plant 



of this description is Spiculeea ciliata, whose rusty 



flowers when spread open may be compared to long- 

 legged spiders, the Hp with a long solid lamina 



looking like their body, while an appendage at its 



apex, which is apparently moveable, is not unlike 



the head of such a creature. 



Orchids are found in almost all parts of the 



world, except upon the verge of the frozen 



Fig. CXXIII.— Megaclinium Bufo; 1. a portion of a spike magnified; 2. flowers in various positions, 

 more magnified. 

 Fig. CXXIII. 6»i. — Spiculaeft ciliata, its flower. 



iX 2 



