LIBRARY 



NEW YORK 



BOTANICAL 



GARDEN 



The taxonomic and morphologic status of 

 Ophioglossum Alleni Lesquereux 

 Arthur Hollick 

 (with plates 10-12) 



About fifty years ago Lesquereux described, without any 

 accompanying illustration, an imperfect fossil plant specimen 

 from the Miocene Tertiary shales of Florissant, Colorado, under 

 the name Ophioglossum Alleni* The description was as follows: 



Leaf, elliptical, narrowed by a curve to the acute base; shorter and broader 

 than in O. vulgatum L., of our time, with the same areolation. 



The leaf is about 3 cent, long (point broken), a little more than 2 cent, 

 broad, marked in the middle by the remnant of a fruiting pedicel . . . 



Subsequently the same author redescribed and figured the 

 specimen under the name Salvinia Alleni,\ and remarked: 

 "By its form, its areolation, its size, all its characters, indeed, 

 it is remarkably similar to Salvinia reticulata Heer. "f His 

 amended description was as follows: 



Leaves oval, rounded in narrowing to the base; lateral veins, none 

 visible, areolae large, irregularly square or equilateral, inordinately distrib- 

 uted. 



Leaf about three and a half centimeters long, twenty-two millimeters 

 broad, of a thin substance, with a thick middle nerve and irregularly quadrate 

 meshes, formed of very distinct black nervilles, the primary ones more or 

 less in right angle to the middle nerve, with oblique, generally parallel vein- 

 lets between them .... 



Later he listed and figured tw r o other, more perfect specimens, § 

 with the following brief comment: 



The species is common and has been obtained in large well-preserved 

 specimens by the different collectors. The leaves are merely variable in size, 

 obtuse or slightly emarginate at the apex, topped by the point of the ex- 

 current nerve. 



* U. S. Geol. Survey Terr., Sixth Ann. Rept. 1872: 371. 1873. 



f U. S. Geol. Survey Terr. Rept. vol. 7 (The Tertiary Flora): 65. pi. 5, /. //. 

 1878. Reproduced on Plate io, fig. i. 



% Flora Tertiaria Helvetiae 3: 156. pi. 145, f. 16. 1859. Reproduced on 

 Plate io, fig. 4. 



\ U. S. Geol. Survey Terr. Rept. vol. 8 (The Cretaceous and Tertiary 

 Floras): 136. pi. 21, f. 10, 11. 1883. Reproduced on Plate io, figs. 2, 3. 



207 



