22 GKAF ZU SOLMS-LAUBACH— MO^^OGKAPH OF THE ACETABULAEIE^. 



when fresh, but after decalciiication easily separable from each other as far as the base of 

 the corona, with the interlocking ribs irregular, but usually together in pairs and 

 increasing in numbers towards the centre, and with Hat but apiculate margin. Segments 

 of the corona superior and inferior similar, narrow, very closely pressed together, deeply 

 bilobed externally, often irregular from the unequal size of the processes, the membrane 

 of which is much thickened. Hair-scars on the parts of the corona superior as a rule 

 in fours, forming a series here and there pushed outwards. Vestibular folds much 

 thickened in the surface view towards the apical membrane, standing out as strong, 

 refractive, round knobs alternating with the rays. 



iSize : diameter of cap 10-lG mm.; breadth of corona superior 0'2G mm. (Plate I. 



fig. 6.) 



It is found on the warmer Anstralian coasts — Edgecumbe Bay, coll. Kilner, Hb. Ag„ 

 Thuret, Strassburg ; Port Bowen, Aiistr. or., coll. A. Dietrich, Hb. Thuret (nomine 

 A. crenulata, var. tricuspidata, Grun. ; a eel. Grunow missa). 



Among the existing descriptions of different Acetahularice, which confine themselves 

 for the most part to the citation of trivial things and are not therefore intelligible 

 without an inspection of the original specimens, Agardh's representation of his 

 A. Kilneri is a notable exception. He has not only rightly recognized the character of 

 the section Acetabuloides, but also the form of the two coronas, and has seen the notch- 

 processes of the side-walls of the sporangial rays, thus pointing out the actual differential 

 characters of his species. 



b, Sporangial rays without apiculum. Segments of the corona not deeply 

 bilobed towards the oiftside. 



3. AcETABULARiA MAJOR, Mautcus, in Preussisch. Exped. nach Ostasien, Bot. Theil, Die 

 Tange, von G. v. Martens, BerHn, 1866. — A. crenulata, var. major, Bonder, Algen 

 d. trop. Australiens, 1871.—^. deniidata, Zanard. Phyceai Papuanae, [N'. Giorn. bot. 

 ItaL 1878, p. 38. 



In habit generally resembling A. Kilneri ; cap large, long-stalked, extended flat, only 

 slightly calcified. Sporangial rays (70-80 in number) united in the calcified condition, 

 but separate from each other up to the base of the corona after decalcification ; notch- 

 processes of the side-walls much less sharply defined ; apices of the rays blunt, cut off 

 straight or somewhat emarginate, wholly without apiculum ; segments of the coroca 

 superior and inferior of similar shape, those of the upper quite narrow, without 

 emargination, each with a single series of about 8 hair-scars, those of the lower with a 

 slight bulging outwards of the margin ; spores seen only in an unripe state and, 

 considering their extraordinary differences in size, a scarcely normal condition. 



Size : diam. of cap 15-20 mm. ; breadth of corona superior 0-18-0-22 mm. • size of 

 spores 0075 mm. 



Hah. On the tropical shores of Eastern Asia. Collected at Sima-haradscha in Siam, 

 in Pebruary 1862 by SchottmiJller (Hb. Berol.) ; Atapapua, Timor (Hb. Strasb.) ; at 

 Warbusi, in Geelvink Bay, Xew Guinea, collected by Beccari, March 1872 (coll. Becc. 

 Strasb.). 



