406 Transactions. — Botany. 



oppositely pinnulate, the lower and upper pinnules of the pinnae 

 somewhat simple, patent, and obtuse, the middle ones compound, 

 with the upper branchlets secund. Cells of the rachis six times 

 longer than broad. Tetraspores in tetrads (?), secund on the 

 pinnules. 



Distribution. — Otago Harbour (Lyall) ; Fuegia, Tasmania. 



I have seen two plants of this type, one from Riverton and 

 one from Port Chalmers, but I cannot identify either with any 

 certainty as belonging to this species, nor am I satisfied that the 

 plant described by Agardh is the same as Harvey's. 



7. Antithamnion (?) confusum, R. M. L. (= CaUithamnion con- 

 fusum, J. Ag., Epicr. Florid., p. 25. Wrangelia squarrulosa, 

 Harv., Fl. Nov. Zel., ii., p. 236. But not Alg. Austr. exs. 

 No. 266.) 



Thallus erect, 15-25 cm. high, with rather lax irregularly 

 alternately pinnate branches, the lower pinnae spreading, the 

 upper distichous with acute axils. Each node provided with 

 whorled ramuli : two lateral ones divaricating, compound, pecti- 

 nate, the branchlets of the ramulus diverging, cuspidate, often 

 reflexed, the outer branchlets sometimes dichotomous at the tip ; 

 two smaller ramuli, often very much reduced, sometimes repre- 

 sented only by a hook-like process, are found alternating with 

 the others. The ramuli do not spring directly from the node, 

 but from a short distance below it, and are connected with 

 it internally by a thread of brightly coloured protoplasm. To- 

 wards the base of the plant the internodes of the main axis and 

 pinna? are completely invested by the ramuli, which are here 

 larger and more decompound, with many of the branchlets more 

 or less appressed to the stem. I have only seen several spor- 

 angia, which were transversely divided into two. and. unless 

 divided again in the plane of the slide, contained only two 

 spores. Antheridia and cystocarps unknown. 



Distribution. — Preservation Harbour {Lyall) ; Catlin's, St. 

 Clair (J. C. S.) ; Wycliffe Bay, The Nuggets {R. M. L.). 



The position of this plant is uncertain, and must remain so 

 until the cystocarps are discovered. Harvey placed it in the genus 

 Wrangelia. Agardh considers that its vegetative structure sug- 

 gests rather the genus CaUithamnion than Ptilota or Wrangelia. I 

 believe that its place will be found in the genus Antithamnion, 

 for it is well provided with the gland-cells (?) so characteristic 

 of that genus, and the probably immature spores which I have 

 Been suggest Antithamnion rather than CaUithamnion. It is, 

 moreover, very similar in structure to such a plant as A. mucro- 

 natum. There can be but little doubt of the identity of my 

 plant with Harvey's, but it is possible that it is not the same as 



