Hepaticae : Yale Peruvian Expedition of 191 1. 



305 



theoretical interest . Apparently here, as in so many species of Plagio- 



chila, terminal branches have been supplanted by intercalary branches, 



and the appearance of a terminal branch is to be looked upon as a 



reversion. It is perhaps associated with a vigorous growth and a 



retention of a juvenile condition, 



much as in the cases described 



by the writer under Cephalozia 



hicuspidata (L.) Dumort. and 



Lophocolea heterophylla (Schrad.) 



Dumort.^ 



Closely related to P. Bing- 

 hamiae is a sterile Ecuador plant 

 collected by Spruce and described 

 by him under the name P. hypan- 

 tra.^ In this species terminal 

 branches although infrequent are 

 the rule rather than the excep- 

 tion. The leaves are similar in 

 form to those of P. Binghamiae 

 but the teeth, especially those 

 in the apical region, are longer 

 and sharper The leaf-cells are 

 characterized by less robust 

 thickenings. In P. patentissima 



Steph.,3 a Peruvian species collected by Lechler at St. Gavan and 

 known to the writer from description only, the leaves bear from 

 eleven to thirteen spines, those near the apex being especially large 

 and acuminate. It differs further from P. Bighamiae in the size of 

 the leaf-cells, those in the middle of the leaf measuring 54 X 27 /« 

 and those at the apex 3G x 27 /<. 



7. Plagiochila chinantlana Gottsche 

 Plagiochila chiantlana Gottsche, Mex. Leverm. 12. pi. 5, f. 1—7. 1863. 

 San Miguel, 5,000-6,000 feet, July 24, 1911. 

 The Peruvian material agrees pretty closely with the specimens 

 collected by Pringle at Patzcuaro, Mexico, and distributed by Under- 

 wood and Cook in their Hepaticae Americanae, No. 110. The species 

 was first collected in the province of Oaxaca, Mexico, by Liebmann. 

 According to Spruce it has been found also by Cross at San Sebastiano, 

 Co 1 ombia , but Steph ani does not record its occurrence outside of Mexico . 



1 Ann. Bot. 26 : 33. 1912. 2 Hep. Amaz. et And. 465. 1885. 



3 Bull, de I'Herb. Boissier II. 2 : 877. 1902. 



Figure 2. — Plagiochila Binghamiae 

 Evans 

 A. Leaf, dissected from the stem, 

 X 17. B. Cells from the middle of a 

 leaf, X 300. C. Tooth from near the 

 apex of a leaf, X 300. The figures 

 were drawn from the type specimen. 



