68 Salisbury. — On the Structure aiid Relationships of 
VIII. General Discussion of the Testa, 
i. The Multiple Origin of the Integument in the Trigonocarpeae. 
The general facts supporting the theory of a multiple origin for the 
integument of the Lagenostomales are well known, 1 and in the Trigono- 
carpean series the integument is also composed of several equivalent units, 
which may well have had a similar origin. We shall therefore briefly 
review the chief testal features which the members of this group exhibit. 
Text-fig. 8. Transverse sections of the seeds of various Trigonocarpeae. Corresponding ribs 
are in each case marked R 1 , R 2 , &c. 
In the genus Trigonocarpus itself T. P arkinsoni had twelve ribs, three primary 
and fissured, three secondary and non-fissured, and six tertiary, opposite which the 
sarcotestal bundles were situated (Text-fig. 8, d). 
In T. corrugatus 2 and T. Shorensis six ribs only were present, of which the 
three non-commissured died out, about half-way up in the former seed and one-third 
in the latter (Text-fig. 8, c). 
1 Oliver and Salisbury: Palaeozoic Seeds of Conostoma. Ann. Bot., vol. xxv, 1911, p. 41. 
2 Renault, loc. cit. 
