Chapter XIII — 229 — Utricularia, Biovularia 



of a more or less aborted branch arising on the upper surface of the 

 chief stolon. This branch always remains delayed in development. 

 The scape produces no rhizoids, nor any scale except in the inflores- 

 cence. 



4. The dichotoma-monanthos type. — To this type belongs a goodly 

 number of species which are purely Australasian, and so far known 

 only from Tasmania, Australia proper and New Zealand. This type 

 is not present in the recent Brass collections of New Guinea plants 

 at the Arnold Arboretum of Harvard University. They are at once 

 recognizable by their winged traps. 



The series includes one freely floating form, U. tubtdala, and while 

 the terrestrial forms are readily divided into two groups, those with 

 runner stolons {U. dichotoma, U. monanthos, etc.) and those which 

 have only anchoring stolons {U. Menziesii, U. violacea, U. volubilis, 

 U. Hookeri), never runners, and which are confined to the extreme 

 S. W. of Western Australia. These have been regarded by Goebel 

 as primitive forms, but the only fact to which this view can be tied 

 is the absence of runner stolons. Allied and included with these is 

 the genus Polypompholyx, with 2 (or probably 4) species. 



Freely floating species. — The only freely floating species of this 

 group known, and that only from herbarium specimens in the Mel- 

 bourne Herbarium (paratypes at Kew and at the British Museum of 

 Natural History), to which I had access, is U. tuhulata. It was col- 

 lected in 1875 by W. E. Armit in "mountain swamps near Cash- 

 mere, 40-50 mi. west of Rockingham Bay" in Queensland, but never 

 since. In general appearance it resembles U. purpurea, but only 

 superficially owing to the whorled position of the leaves (j(5 — 10, 11). 



The "rather long" stolons bear leaves and traps in whorls, in each 

 whorl four leaves alternating with four traps on long stalks, so ori- 

 entated that usually two of the leaves he on one side and two on 

 the other side of the stolon, the traps being then one dorsal, one 

 ventral, and one on each side. Occasional departures from the rule 

 may be observed when two traps may stand side by side, or two 

 leaves. In the mature condition the leaves and traps are joined 

 at their bases to form a complete ring of tissue surrounding the node 

 from which they arise. A dissection of several terminal buds showed 

 clearly that the primordia of the lateral organs are all quite distinct 

 at first, so that the ring supporting them is secondary. The primor- 

 dia appear at first as low mounds of tissue in transverse series of 

 eight, at first indistinguishable from each other. At about the sixth 

 node the leaves elongate somewhat, overpassing the traps in growth. 

 The apex of the axis is long, naked and slightly circinate. The pri- 

 mordia are not at all crowded. In the axil of a leaf a bud which 

 develops into a branch stolon may arise. Traps with their stalks and 

 leaves attain a length of 2 cm. The leaves are flat, hnear and apicu- 

 late, the trap stalk foliose (Lloyd 1936c). 



According to von Mueller, the scape is terminal on a chief 

 shoot and such evidence as I was able to obtain bears out this view. 

 I dissected one terminal bud to find that it was indeed an inflores- 

 cence with a lateral vegetative bud. Slender at the base, it swells 

 considerably at or above the middle to form a spar-buoy float. The 



