The Ohio ^N^aturalist, 



PUBLISHED BY 



The Biological Club of the Ohio State Uni'versity, 

 Volume IX. FEBRUARY, 1909. No. 4. 



TABLE OF CONTENTS. 



Griggs— The SporophylLs of Lessoniopsis ■ 437 



Jennings— Some New or Otherwise Noteworthj' Plants from Ohio 440 



Patton— A Sj-nouymical Deflnition of Ny.sson and of N. auriuotus 442 



SCHAFFNER— The Classification of Plants, IV 446 



McCray— Meeting of the Biological Club 455 



THE SPOROPHYLLS OF LESSONIOPSIS. 



Robert F. Griggs. 



In a former paper on the development of LessoniopsLs litoralis 

 (Griggs '09), the writer pointed out the fact that the division of 

 the lamina by a basal perforation characteristic of the subfamily 

 is always symmetrical involving the midrib and giving rise to 

 two similar laminae each with a midrib in its centre. In siich 

 a process there is no place for the formation of sporophylls which 

 lack the midrib. Since the former account was written material 

 has come to my attention which shows the origin of sporophylls. 

 This is a medium sized plant collected at the Minnesota Seaside 

 Station early in July. Most of the sporophylls are already full 

 grown but there are a number, especially on the smaller branches 

 around the base of the plant, in all stages of development. 



From branches with sporophylls of different ages it is at once 

 apparent that they correspond with the sporophylls of such 

 kelps as Alaria and Pterygophora. They are not cut off by 

 splits in the transition region like the sterile laminae, but are 

 outgrowths from the meristem below the base of the laminae. 

 The youngest are mere knots roughening the edge of the stipe. 

 These grow outward as in Pter3'gophora with scarcely any flat- 

 tening till thc}^ reach about 1 cm. in length (fig. 1). But soon 

 they begin to expand and each becomes a sessile spatulate blade 

 (fig. 2). Under the protection of the surrounding laminae they 

 reach about a decimeter in length (fig. 3) before the erosion of 

 the waves begins to destroy the rounded tips. Up to this age 



* Contributions from the Botanical Laboratory of Ohio State Uni- 

 versity, XXXIX. 



437 



