602 SEED 



development may be studied in fr. of Enonymus. Arillate seeds in 

 Celastraceae, Commelinaceae, &c., Dilleniaceae, Myristica, Nymphaea- 

 ceae, Passiflora, Sapindaceae, Taxus, &c. In Euphorbiaceae the aril 

 remains small and hard and is called a caruncle, but usu. it is fleshy. 

 The endosp. may be starchy, farinaceous, floury, or mealy (the 

 cells containing starch and when powdered forming a floury dust) as 

 in Triticum, oily as in Papaver, Ricinus, &c., fleshy as in Berberis, 

 horny as in Coffea, bony as in Phoenix and Phytelephas, ruminate 

 (marked by wavy transverse lines which give it a marbled look) as in 

 Anonaceae, mucilaginous, &c. 



The embryo (rarely embryos) may be straight, curved, twisted, &c. 

 (and cf. Cruciferae). It may have one, two, or several cotyledons (im- 

 portant in classification), or rarely none, as in Cuscuta, &c. 



Mention must be made of adventitious embryos of Alchornea, 

 Funkia, Nothoscordum, &c., and of the peculiar cases of Ginkgo, and 

 Gnetum, where the seed 'ripens' before fertilisation. 



Seemannaralia R. Viguier. Araliaceae (i). i S. Afr. 



Seemannia Regel. Gesneriaceae (n). 5 Peru, Bolivia. 



Seetzenia R. Br. Zygophyllaceae. i Afr., As., in deserts. 



Segetalis (Lat.), growing in grain fields. 



Segments, the free portions of a concrescent K or C. 



Segregate, kept separate. 



Seguieria Loefl. Phytolaccaceae. 25 S. Am. L. leathery; stipules 

 thorny. Powerful odour of garlic. Cpl. i. Fr. a samara. 



Seidelia Baill. Euphorbiaceae (A. n. 2). i S. Afr. 



Seidlitzia Bunge et Boiss. Chenopodiaceae (B). i Armenia, Persia. 



Selagineae (Bff.). See Scrophulariaceae and Globulariaceae. 



Selaginella Spring. The only genus of Selaginellaceae. 700 chiefly 

 trop. ; a few temp. e.g. selaginoidcs Link on boggy hill sides in Brit. 

 Most live in damp places, esp. in forests, but a few xero. The embryo 

 has a suspensor, and grows directly into the leafy plant which shows 

 a habit very similar to Lycopodium much-branched stem, often 

 creeping, bearing roots on lower side and 1. on upper, with term, 

 cones of sporangia. L. spirally arranged as in most Lycopodiums 

 (e.g. in S. selaginoides], or more commonly in 4 ranks, two outer ones 

 of large, two inner ones of small L, thus giving the stem a dorsiventral 

 structure. The roots in some, e.g. S. Kraussiana A. Br. and S. 

 Martensii Spring, are borne on rhizophcres, anomalous stem branches 

 developed at the nodes and exhibiting a sort of intermediate structure 

 between stem and root. The sporangia are placed at the bases of the 

 1. in term, cones of radial symmetry. The mega-sporangia contain 

 4 large spores and can easily be distinguished by eye. On germ, a 

 microspore produces a rudimentary S prothallus bearing an anthe- 

 ridium. The megaspore forms a ? prothallus, which remains en- 

 closed in the burst spore, and has an upper small-celled green portion 

 and a lower large-celled storage portion as in Salviniaceae, &c. 



S. lepidophytta Spring is a xero. which curls into a ball in the 

 dry season, and may be rolled about by wind (cf. Anastatica). 



Selaginellaceae. Lycopodiales. Only genus Selaginella (q.v.). 



Selago L. Scrophulariaceae (n. 7). 140 S. and trop. Afr., Madag. 



Selenia Nutt. Cruciferae (2). 2 S.W. U.S. 



