C. H. Ostenfeld: Contributions to West Australian Botany. I. 19 



long and 2.0 — 2.2 mm thick, and the pollen sacs were not at 

 all twisted. There is thus a slight difference in shape between 

 the male flowers of the two species, but nothing to justify the 

 statement by Ascherson that the flowers of C. manatorum are 

 twice as large as those of C. isoetifolia \ 



As regards the female flowers I have not found any dis- 

 cernible difference between the two species. They have the same 

 size and the same shape (see Fig. 8 b of C. isoetifolia). On the 

 other hand there seems to be a distinctive character in the size 

 of the fruits as already given by Ascherson (1868). 1 have 

 measured ripe fruits of C. manatorum from Cuba which were 6 mm 

 long (the beak not included), and unripe (?) fruits of C. isoetifolia 

 from India (the Australian specimens were in flower only) were 

 3.5 mm long; also their shape is somewhat different, viz.: oblique- 

 obovate in C. manatorum and oblique-elliptic in C. isoetifolia. 



Summarising, we must admit: (1) that the Indo-pacific C. 

 isoetifolia and the Caribbean C. manatorum are very near in charac- 

 ter; (2) that most of the distinctive marks hitherto given do not 

 hold good; (3) that small differences in the anatomy of the 

 leaves and in the size and shape of the anthers and fruits make 

 it possible to retain them as distinct species. 



3. Cymodocea antarctica (Labill.) Endl., 



Genera plant. (1836) 230; Ascherson, in Das Pflanzenreich IV, 11 (1907) 151; 

 C.zosterifolia F. v. Müller, Census of Austr. Plants (1882) 121; Ruppia antarct. 

 Labillardiére, I.e. (1806) 116, tab. 264; C aulinia antarct. R.Br., Prodr. Nov. 

 Holl. (1810) 339; Amphibolis bicomis CA. Agardh, Spec. Algar. I, 2 (1822) 

 474; A. zosteræfolia C. A. Agardh, 1. c. 475; Gaudichaud, 1. c. (1826) 35 et 

 161, pi. 40, fig. 2 ; A. antarct. Sonder et Ascherson, Linnæa 35 (1867) 164; 

 Pectinella antarct. I. M. Black, Transact. Roy. Soc. South Australia, XXXVII 

 (1913) 1, pi. I et ibid. XXXIX (1915) 94; P. Griffithii I. M. Black, 1. c. (1915) 94. 



As already stated in the present paper (p. 6), this charac- 

 teristic species is common along the southern part of the West 

 Australian coast. I saw it in the Cave district (No. 267), at 

 Cottesloe beach, at Geraldton (No. 264), and at Carnarvon, Sharks 

 Bay (No. 265). Labillardiére (1. c.) reports it from Cape Leeu- 

 win, Harvey (1. c.) from King George's Sound, Rottnest Island 

 and Fremantle, Gaudichaud (I.e.) and Naumann (see Ascherson 



1 He says (Sitzber. Naturf. Freunde, 20. Oct. 1868) that C. manatorum 

 "besitzt lineale, fast 0.01 m lange Antheren, welche sich von den ovalen 

 kaum 0,003 m langen der C. isoetifolia noch auffaldendep unterscheiden 

 als dies bei den weiblichen Blüten der Fall war". 



2* 



