02 



6. NOTES ON TREUIUA INSIGNIS, GOEBEL. 



By L. Rodway, Government Botanist. 



(Read July 10, 1911.) 



This hepatic was discovered by Goebel in Java, and 

 described by him as recently as 1891- It was subsequently 

 recorded from Tahiti, Samoa, and New Zealand, and now I 

 have gathered it in dense woods on the southern slopes of 

 Mt. Wellington, near the end of Strickland Avenue, and 

 also near Forked Creek. Specimens have been forwarded 

 to Stephani, who ccnfirmsi tlie identification. 



The plant is bright green when fresh, grows flat on the 

 ground, and bears few lateral branches; it is about one 

 centimetre diameter, and about five centimetres long, but 

 it has been recorded from Java of a length of sixteen centi 

 metres- The stem is broad and flat, and bordered on each 

 side by oblong, leafy expansions which, at least in the an- 

 terior portions, are arranged in a succubous manner. Ihai 

 is, the anterior margin of each leaf is depressed and over- 

 lapped by the posterior mai'gin of the one in front of it. 

 On the dorsal surfaces there are two rows of suborect, trans- 

 verse, green bracts, one near the anterior margin of each 

 leaf. These bracts in the Tasmanian form are subquadrate, 

 and about 2 mm. long; in the Javan specimens they are 

 shorter. In the species ITcpaticarum, Stephani refers the 

 New Zealand form to a distinct species, T. bracteata, prin- 

 cipally on account of the bracts being subquadrate, longer 

 than broad, and appressed. On the under surface the plant 

 bears a quantity of thick pellucid mucilage that affords 

 protection to the growing apex, provides moisture in dry 

 periods, and assists in anchoring the plant- This mucilage 

 is secreted by glandular ti.ssue formed on the lower poi-tion 

 of the anterior margins of the leaves. Treubia is generally 

 classed with Aneura, Metzgcria, and Symphyogyna, and like 

 ♦^hem it has a complete absence of perianth ; the work of 

 that organ is undertaken by the enlarged fleshy calyptra. 

 The archcgonia are formed under the bracts. After fertili- 

 sation the calyptra enlarges enormously, becomes clavate, 

 erect, and about one centimetre long- The seta is long, 

 often as much as 5 cm. ; the capsule is spherical, and 

 bursts to the base into four valves. 



