THE TASMANIAN PLOEA. 63 



4. H. CALLICAEPA, Bv/Tige. Small, slender, usually prostrate and spreading. 

 Leaves mostly \ inch, diameter, of 3 or 5 cuneate toothed segments. Flowers in. 

 small umbels, usually 6-10, very minute, each on a short stalk that lengthens 

 considerably under the fruit. Fruit ^-| line broad, smooth, the intermediate 

 rib prominent, curved, with a conspicuous pit in front of it. S. tripartita, Hook. 



Near Launceston, Greorge's Bay, near Hobart in many parts, Longley. 

 Probably common in di-y soil, but overlooked. It occurs throughout Southern 

 Australia. Fl. Nov.- Jan. 



5. H. CAPiLiiAEis, F. e. M. A minute, slender annual. Leaves deeply 3-lobed. 

 Flowers shortly stalked, few together in a small head on a common stalk. 

 Fruit about | line broad, the intermediate ribs very prominent, the space 

 between them and the dorsal rib filled with a swollen, pitted development. 



Pleasant Boat Harbour, George's Bay ; also in Victoria, South Australia, 

 .and West Australia. Fl. Nov.-Jan. 



6 . H. ASIATICA, D. C. Sniall, prostrate, and creeping. Leaves mostly cordate, 

 •obscurely toothed, J-inch long, smooth, on rather long stalks. Flowers 3-4 

 together, purple. Bracts well-developed. Fruit about 2 lines diameter. 



Very common in swamps. Throughout Australia, New Zealand, and most 

 warm parts of the globe. Fl. Nov.-Mar. 



2. TRACHTMENE. 



Fruit laterally compressed, dorsal rib prominent, lateral ones faint, about as 

 broad as long. CaLyx obsolete. Umbels terminal. 



Principally Australian, extending to New Caledonia and Borneo. Differing 

 from Hydrocotyle in habit and in not possessing stipules. 



Lower leaves divided into segments ... ... ... 1: T. australis. 



Lower leaves lobed ... ... ... ... ... 2. T. humilis. 



1. T. AUSTBALfs, B. An erect herb, 1-2 feet. Leaves at the base deeply 

 <iivided into 3-5 much-divided, toothed segments. Umbels many, lateral or 

 terminal, many-flowered. Flowers small, white. Fruit flat, about 1 line, often 

 unequal. Didiscus pilosus, H. 



Hnon, and in many parts in the north and east. Extra-tropical Australia. 

 Fl. Nov.-Feb. 



2. T. HUMILIS, B. Erect, 3-6 inches. Leaves radical, long-stalked, ovate or 

 •oblong, entire or 3-5-lobed, ^-1 inch long. Stem about 4-6 inches, bearing a 

 single terminal umbel. Fruit flat, smooth, 1^-2 lines diameter. Didiscus 

 humilis, H. 



Sub-alpine, Ben Lomond and northern hills. It occurs also in Victoria and 

 New South Wales. Fl. Dec-Jan. 



3. XANTHOSIA. 



Fruit laterally compressed, dorsal rib obtuse, lateral ones fairly prominent, 

 somewhat longer than broad. Sepals fairly developed. Umbels few, flowered, 

 lateral or axillary. Bracts conspicuous. 



Limited to Australia. 



Shrubby. Leaves with obtuse lobes ... ... ... 1. X. pilosa. 



Slender, decumbent. 



Leaf-segments few, broad ... ... ... ... 2. X. pusilla. 



Leaf -segments numerous, narrow .., ... ... 3. X. dissecta. 



1. X. PILOSA, Riidge. Erect or depressed, branched under-shrub, 6 inches to 2 

 feet. Leaves variable, usually divided into few obtuse lobes, hairy and white 

 beneath, about 1 inch long. Flowers 1-8, in small, nearly sessile, lateral 

 umbels. Bracts large and white. Petals narrow, small, white. X. montana, H. 



