Marine Algae.] SUBANTARCTIC ISLANDS OF NEW ZEALAND. 523 



Ceramium stichidiosum, var. scopulorum. 



General description as for C. stichidiosum, var. Smithii, but differing in the 

 following points : A larger plant, 4-6 cm. high, dark red in colour (Klinksieck's 

 " Code des Couleurs," No. 578), much more luxuriant, denser in growth, and differing 

 much in general appearance from the preceding, but scarcely to be distinguished 

 from it by any important diagnostic character. The tips of the pinnae end in a 

 pencil of acuminate pinnules, owing to the repeated dichotomous branching of the 

 terminal and subterminal segments, the forks remaining very narrow, not so densely 

 clothed with prolifications as the preceding. 



The cortication seems to present certain differences from the preceding, but 

 these are perhaps due to the more luxuriant growth of the plant. The whole plant, 

 except the young pinnules and prolifications, is completely corticated by threads 

 consisting of minute cells which are developed upwards and downwards from the 

 larger cells covering the nodes. The interspaces between the cells give to the inter- 

 nodes a more or less longitudinally veined appearance. On the internodes of the 

 young pinnules transverse hyaline lines are sometimes seen. Tetraspores as in 

 C. stichidiosum, var. Smithii. Cystocarps solitary or in pairs in the axils of the sub- 

 terminal pinnules. (Plate XXIV, fig. 2, represents a fragment of frond of C. stichi- 

 diosum, var. scopulorum, magnified to show cystocarps.) 



* The Snares ; J. C. S. ! 



MiCROCLADiA, Greville. 



Distribution. — Most seas. 



Microcladia pinnata, J. Ag., Anal. Algol., cont. iv, p. 34, 1897. 



Enderby Island ; J. C. S. ! (New Zealand ; R. M. L.) 



The species is scarcely to be distinguished from the northern M. CouUeri ; but, 

 as no description of it has been given in any publication dealing with New Zealand 

 plants, I append one. 



Thallus 15-20 mm. long, filiform, compressed, the whole distichously, rather 

 laxly, alternately decompound. Lower pinnae rather distant, 1-2 cm. apart, alternate 

 elongate, generally not much branched, and with the secondary pinnae and pinnules 

 about lanceolate in outline. Ultimate pinnules acute, and coming off at an angle of 

 about 45° or more from the pinnae. The lower pinnae are set at about right angles 

 to the main stem, but the upper ones become less and less divergent. The main 

 stem and pinnae are sometimes provided with two series of distichous simple or 

 subsimple prolifications 1-3 mm. in length. In some forms these are wanting, and 

 the main stem is completely glabrous. The tetraspores (not hitherto described) are 

 in tetrads, subterminal in the ultimate pinnules, at first completely immersed, but 

 afterwards partially extruded, and more or less irregularly arranged, generally in 

 irregular longitudinal series along both margins of the thallus, sometimes appearing 

 to be pseudo-verticillate and at other times scattered, the arrangement varying 

 in different parts of the same frond. The cystocarps are terminal or subterminal, 

 sessile or shortly stalked, black in dried specimens, and surrounded by a more or less 

 completely developed involucre of ramuli. 



