306 Transactions. — Botany. 



according to Mr. F. 0. Bower, ("Jour. Mic. Sc," Jan., 1880,) 

 is partly formed by invagination, and partly by deliquescence. 

 In Adenucijstis, too, these conceptacles are as wide at the mouth 

 as at the base ; but in most, if not in all the Fucacece, the aperture 

 of the fertile conceptacle is much narrower than the interior. 

 The conceptacle of Adenocystis, therefore, may be homologous to 

 the " Fasergriibchen " of Alaria esculenta and Fucus platy carpus. 

 (Vide Keutz. " Phycologica Generalis," p. 92.) 



When young, the frond of Adenocystis is dotted over with 

 tufts of colourless hairs, which encircle the mouths of the con- 

 ceptacles. A transverse section through the bladder- wall of a 

 not fully matured specimen, shows the frond to be covered with 

 short clavate bodies, in which the cell contents are aggregated 

 together into several distinct masses. It is to these Hooker 

 refers, when he says that " the frond is coated with a thin layer 

 of vertical clavate articulate filaments." A section through the 

 frond of a mature specimen shows it to be covered with three 

 different kinds of bodies : — 



(a.) A number of short clavate filaments, similar to those 

 already mentioned. 



(6.) Somewhat longer jointed hairs, probably developed 



from (a), 

 (c.) Oval sacs, containing zoogonidia (?) 

 These are all represented in fig. 1. 



The plant is a common annual, found chiefly in tidal pools. 

 It cannot be obtained during the months of June, July, and 

 August. 



8. Ecklonia radiata. 



The generic description in the " Handbook of New Zealand 

 Flora" is : " Eoot scutate or dividing into short fibres. Frond 

 olive-green, pinnatifid, ecostate, segments produced from the 

 magnified teeth of a simple lamina, which is contracted to a 

 solid or inflated stem at the base. Sori superficial on the lower 

 part of the pinnae of narrow ellipsoid spores, mixed with clavate 

 inarticulate filaments." (Sp. radiata:) "Frond 1-2 feet long, 

 stem solid or sparingly inflated." 



The stem consists of three tissues : an epidermal layer of 

 coloured cells, a second layer of parenchymatous tissue, and a 

 third of loose cells, lying in mucilage. In the second tissue, just 

 beneath the epidermal cells, there is a circular ring of longitudinal 

 " secretion canals," which probably act as conducting or storing 

 vessels for the mucilage, for when a fresh stem is cut through, 

 mucilage exudes from them in considerable quantity. These 

 canals are formed by the splitting away of adjacent cells, and 

 appear first as small irregularly shaped openings in the tissue, 

 some distance from the apex of the frond. As they increase in 



