266 NATURAL HISTORY OF PLANTS. 



cymes. Their habit is often quite pecuHar. Grusea, American, has 

 narrow and elongate calycinal divisions ; a corolla of Spermacoce 

 generally tetramerous and rather large ; a bilocular ovary with short 

 divisions or scarcely distinct. The fruit divides into two indehiscent 

 cocci. They are herbaceous plants, the compound terminal cymes 

 of which resemble capitules and are surrounded by two pairs of large 

 bracts forming an involucre. In Emmeorhiza, sub shrubby and volu- 

 bile plants of tropical America, the cymes, much branched, resemble 

 the inflorescences of Riihia proper ; and the tetramerous flowers are 

 nearly those of Spermacoce, with a style of two shallow terminal 

 divisions, and a fruit whose two monospermous cocci open inwards, 

 like those of PsijUocarpus. 



Hjjdrophylax and Ernodea, the flower of which is nearly that of a 

 Grusea or a Diodia, axillary, solitary or nearly so, and rather large 

 for this group, differs also from all the preceding types in its fruit 

 being indehiscent ; the two cocci, much compressed and with flat 

 face, can only be separated artificially. The deep divisions of the 

 calyx are ordinarily four in number, two of which are lateral (more 

 rarely five or six). The corolla has a long narrow tube and valvate 

 Limb. The true Hydroplujlax grows in the maritime sands of tropical 

 Asia, Madagascar, and southern Africa. The summit of the style is 

 a little enlarged and obscurely bilobed, and the exocarp is suberose. 

 Ernodea, with us only a second section of the same genus, has the 

 summit of the style somewhat enlarged and a less consistent exocarp, 

 more distinct from the cocci ; it inhabits the coasts of the Antilles 

 and Florida. 



III. ANTHOSPERM SERIES. 



The Anthosperms ^ (fig. 237, 238), which have given name to this 

 series, are not always its most perfect representatives, because the 

 flowers are not ordinarily hermaphrodite, but unisexual. In those in 



1 Anthospermum L. Hort. Cliff, t. 27 ; Oen. Frodr. iv. 579. — Endl. Gen. n. 310o.— B. H. 

 n. 1164.— J. Gen. 197.— G^iUTx. r. Frucf. iii. Gen. ii. 140, ,n. 204,.—Touhe/ortia Poxted. 

 87, t. 195.— A. Rich. Eub. 58, t. 2, fig. 1.— DC. Fpist. 11 (ex Endl.). 



