OF ARTS AND SCIENCES. 195 



VII. 



CONTRIBUTIONS FROM THE CRYPTOGAMIC LABORATORY 

 OF THE MUSEUM OF HARVARD UNIVERSITY.* 



v. — ON THE ANATOMY AND DEVELOPMENT OF 

 AGARUM TURNERI, Post. & Rupr. 



By James Ellis Humphrey. 



Presented June IG, 1S86. 



The family of Laminanacea3 includes several genera of large, coarse 

 marine alg e of an olive-brown color and leathery substance. In 

 most of these, the thallus shows a distinct differentiation into stipe 

 and lamina, and is attached to the substratum by branched, root-like 

 processes, or rhizoids. This family contains forms which are the 

 largest of Thallophytes, and indeed among the largest of plants. 



Not to mention several contributions by earlier writers on the 

 Algre, three papers have recently been published which deal with the 

 anatomy of Laminariacete, all by German writers and including ob- 

 servations on four genera. Reinke has described the anatomy of 

 Laminaria saccharina, L. digitata, and Alaria escidenta ; f Will, that 

 oi 3Iacrocystis luxarians ; % and Grabendorfer, that of Lcssoma ovata.% 



* The studies whose results are here recorded were carried on in the Cryp- 

 togamio Laboratory of Harvard University, under tlie direction of Dr. W. G. 

 Farlow. 



The following are the titles of the preceding papers of this series : — 



1. Notes on some Species in tlie Tliird and Eleventh Centuries of Ellis's North 

 American Fungi, Proc. Am. Acad , XVIII. G5-S5. 



2. The Cryptogamic Flora of the Wliite Mountains. Appalachia, III. 2.32-251. 



3. Notes on some Species of Gymnosporangium and Chrysoniyxa of the 

 United States. Proc. Am. Acad., XX. 311-323. 



4. Notes on Arctic Algae; based principally on Collections made at Ungava 

 Bay by Mr. L. M. Turner. Proc. Am. Acad., XXL 469-477. 



t Beitrlge zur Kentniss der Tange, — Pringslieim's Jahrbiicher fiir wiss. 

 Botanik, Bd. X. p. 371, 1876. 



J Zur Anatomie von Macrocystis luxurians, — Botanische Zeitung, 42 Jahr- 

 gang, p. 801, 1884. 



§ Beitrtige zur Kentniss der Tange, — Bot. Zeit., 43 Jahrgang, p. 641, 1885. 



