36 Humphrey . — The Development of the 
In the Zingiberaceae the striking differentiation of the 
inner layer of the testa forms the most marked common 
character. Costus differs from other genera examined in the 
form of its aril and in the histological character of its micro- 
pylar collar and lid. The form of the chalazal mass shows 
interesting variations ; and studies of other genera are likely 
to prove very interesting, possibly indicating lines of descent 
within the family. 
In respect to seed-development, the Musaceae are a hetero- 
geneous group. Perhaps the nearest affinity with the Zingi- 
beraceae is shown by Musa . Strelitzia lacks the most 
characteristic Scitamineous feature, the micropylar collar 
and lid, but is, in a measure, saved by its aril. In Heliconia, 
the supplanting of the testa by the endocarp precludes the 
supposition of a close affinity with the other genera. 
List of Writings Referred to. 
Brown, R., ’10: Prodromus Florae Novae Hollandiae. London, 1810. 
Eichler, A. W., ’84 : Beitrage zur Morphologie und Systematik der Marantaceen. 
Abhandl. d. k. Akad. d. Wiss. zu Berlin, 1883, h P- L 7 pL 1884. 
Gaertner, J., 1788- 91 : De fructibus et seminibus plantarum. T. I ; Stutt- 
gardiae, 1788 : T. II, Tubingae, 1791. 
Gris, A., ’59 : Note sur le fruit et la graine des Maranta indie a , Thalia dealbata , 
et Calathea villosa. Bull. Soc. bot. de France, T. VI, p. 737, 1859. 
* ’60 : Origine et mode de formation des canaux perispermiques dans les 
Marantees. Bull. Soc. bot. de France, T. VII, pp. 237, 875, i860. 
’60 a : Note sur l’origine et le mode de formation des canaux perisper- 
miques dans la graine des Marantees. Ann. Sci. Nat., Bot., 4® Ser., 
T. XIII, p. 97, 2 pi., i860. 
— ’64 : Recherches anatomiques et physiologiques sur la germination. 
Ann. Sci. Nat., Bot., 5® Ser., T. II, p. 1, 4 pi., 1864. 
Gruss, J., ’95 : Die Diastase im Pflanzenkorper. Ber. d. d. bot. Ges., Bd. XIII, 
p. 2, 1 Taf., 1895. 
Guignard, L., ’82 : Recherches sur le sac embryonnaire des Phanerogames 
angiospermes. Ann. Sci. Nat., Bot., 6® Ser., T. XIII, p. 136, 5 pi., 1882. 
*93 : Recherches sur le developpement de la graine, et en 
particulier du tegument seminal. Journal de Botanique, T. VII, p. t, 
1893. 
