TYPE 17. GRAINS COMPOUND, HOLLOW-SPHERICAL. 293 



Rcauimiria verimculula. (Tuniariscinccr.) Dry cmlos-perm. — Compound gi-iiins rounded, ov.il, ellip- 

 tical, oblong, conical; one-half to as thick as long, sometimes by pressure poljdicdral, granular 

 or reticulate, consisting of (jver 700(J components. Length alxjut 31/j, thickness about 20yu. 

 The smaller separated-grains almost spherical, larger ones rounded-angular or polyhedral, 

 compressed into the shajie of a disk. Breadth 1 to Ofx, thickness 1 to 1.5/^. 



Moacurra sp. (Diclui-pelacem.) Dry cotyledons. — Separated-graius rounded and rounded-angular to 

 polyhedral; the larger ones have a small central cavity. Size 1 to 5;i. Compound grains 

 (few distinct) rounded or oval, consisting of 2 to about 40 components. Size 12/i. 



Dipteryx odorata Wilkl. {Leguminosce.) Dry cotyledons. — Comi)ound grains rounded, rarely oval, 

 frequently somewliat irregular or angular, granulated or reticulated-granular, consisting of 

 4 to about 60 components. Size 10 to 12/^. Separated-grains few (since the compound 

 grains do not fall apart easily), romided-angular, the larger ones with a small cavity. Size 

 2 to 4/i. The starch-gi-ains are embedded in the protoplasm and are rather crowded. 



Enkida gigalobium DC. {Leguminosce.) Dry cotyledons. — Compound grains rounded, oval, low cone- 

 shaped, frequently somewhat angular or irregular, granulai', consisting of 10 to over 200 

 components. Size about 12/z. Few separated-grains (the compound ones not falling apart 

 easily), rounded or rounded-angular. Size 1 to 2.5ju. 



Type 17. Grains Compound, Hollow-Spherical. 



Grains hollow, at first homogeneous, afterwards formed by means of radial fissures into a 

 globular shell-like layer, consisting of 12 to over 100 components, which rarely are entirely separated 

 from each other. These grains are best known in Zygnemacece and Desinidiacew, but also occur 

 in other low forms of Algce. They have a globular or spheroidal -shape, and at fu-st appear as a 

 homogeneous ring which is afterwards broken by radial fissures. They are always embedded in 

 chloroplasts and inclose protoplasm in their hollow spaces. They rarely fall apart into rounded or 

 angular separated-grains. 



Closteriwn lanceolatum Kutz. (Algce.) Fresh seed. — Separated-grains disk-shaped or cuneiform, angu- 

 lar and usually irregular, strongly compressed. Size about 7m. They fill a conspicuous median 

 cylindrical space in the entire length of the cell and probably arise by the breaking up of 

 the inner spheres which are no longer present. Other specimeiis show the spheres Ijut no 

 separated-grains. 



Spirogyra jugalis Kutz. (Algce.) Fresh seed. — Compound grains consisting of 14 to about 40 com- 

 ponents. Size about 11/u. 



Spirogyra urthospira var. spiralis Nag. (Algw.) Fresh seed. — Compound grains consisting of 12 to 

 about 30 components. Size about lOyu. 



Zygnenia cruciatum Ag. (Algce.) Fresh seed. — Compound grains consisting of 40 to over 100 com- 

 ponents. Size about 17ju. 



Mougeotia gracilis Kutz. (Sterculacece.) Fresh seed. — Compound grains consisting of 10 to about 50 

 components. Size about 12/i. 



