C. H. Ostenfeld: Contributions to West Australian Botany. I. 13 



point. Nevertheless, in several minor points a transverse section 

 of a leaf-blade of C. angustata is characteristic and makes it pos- 

 sible to distinguish this species from the three others. Fig. 2 shows 

 that the lacunae (air chambers) of the leaves (marked x) arc 

 small and narrow, much smaller than in the other species; this 

 is correlated with the lesser thickness of the leaf and the fewer 

 layers of cells inside the epidermis. The tannin (?) idioblasts 

 (dotted in the fig.) of the epidermal layer are numerous, and cells 

 of the same kind occur sometimes in the interior of the leaf. 

 The veins do not show any difference from those of the other 

 species, but it is noteworthy that the sclerenchyma is very poorly 

 developed: just inside the leaf-margins a small sclerenchyma-strand 

 is found, and on both sides of the central vein small subepidermal 

 sclerenchyma-strands are present, while such strands are absent 

 beside the other veins. A comparison of my 

 figures with those of Sauvageau will make the 

 differences clear better than a long explanation. 

 I have not succeeded in finding the male 

 flowers; but judging from the near relationship 

 to the other species it is probable that the male 

 flowers are much alike. Thus we should expect pig. 3. Cymodocea 

 the male flower of C. angustata to be a terminal angustata a Apex 

 . . „ , ~, i o i i °f a leaf- b Female 



one, consisting of a long filament and an 8-locular flower ( 4 / 3 nat. size). 



anther, i. e. really two connate stamens. 



The female flower consists of two free short-stalked carpels, 

 each surmounted by a short style and two very long thread-like 

 stigmas (Fig. 3 b). The upper parts of the stigmas protrude out 

 of the leaf-sheath while the rest of the flower is inclosed by it. 

 As seen in fig. 1 the long stigmas have sometimes difficulty in 

 finding their way out of the sheath and become much bent or 

 coiled. After fertilisation the carpels begin to grow out and the 

 upper part of the stigma dies away. In one specimen I found 

 one carpel half-grown and the other broken off (Fig. 1). The young 

 fruit was compressed and nearly round in circumference, with a 

 curved beak, not oblique as in the fruits of C. nodosa and C. ro- 

 tundata. In another specimen (that with the flower) a pair of 

 fruit-stalks were present while the fruits themselves had disappea- 

 red. The fruits have a thin fleshy layer outside the hard endo- 

 carp. I have not seen the ripe fruits. 



1 C. Sauvageau, Observations sur la structure des feuilles aquatiques. 

 — Journ. de Botanique, t. IV (1890). 



Idem: Sur les feuilles de quelques monocotylédones aquatiques. — 

 Ann. sc. nat. VII ser. Bot. t. 13 (1891), 103-296. 



