140 Lake Maxinkuckee, Physical and Biological Survey 



The alga? obtained by the plankton hauls of 1899 and 1900, 

 along with a few others collected by hand were identified by Dr. 

 George T. Moore, then associated with Dartmouth College, later of 

 the U. S. Department of Agriculture, now the Director of Mis- 

 souri Botanic Gardens, and the originator of the scheme of keep- 

 ing the algse within bounds by the use of copper sulphate. 



A part of the diatoms collected in the plankton hauls of 1901, 

 as well as various samples of hand gathered material, were identi- 

 fied by Dr. Albert Mann then of the U. S. Department of Agricul- 

 ture, now of the Carnegie Institution of Washington. Some of 

 the alcoholic Characea? material sent along with the plankton 

 were identified by Dr. George T. Moore, while much of the alco- 

 holic and all the dried Chara material was kindly identified by 

 the late Prof. C. B. Robinson of the New York Botanic Garden. We 

 wish here to express our appreciation of the assistance so gener- 

 ously renedered by these specialists. 



During the summer and autumn of 1906 a fair number of tow- 

 ings and hand collections were made, 113 in all, in all sorts of con- 

 ditions, chiefly about shore. This material has been very hastily 

 examined and a number of the more easily recognized forms identi- 

 fied, leaving a large number of the more critical species untouched. 

 Much of the coarser algse obtained were unfortunately sterile, and 

 the species accordingly problematical ; they show a great diversity 

 of species and suggest a very interesting and fruitful field for col- 

 lection and research. 



The collections taken in the various plankton hauls of 1900 and 

 1901 are so very similar that a general statement will suffice, leav- 

 ing any individual peculiarity to be considered in the discussion of 

 the species. 



The following are the most abundant plankton species, having 

 been taken in almost every haul: Lyngbya aestuarii Liebmann, 

 Coelosphaerium keutzingianum Naegeli, Anabaena flos-aquae 

 Brebisson, Eremosphaera viridis de Bary and Ceratium macroceras 

 Schrenk. Among the less common forms are Pediastrum boryanum 

 Meneghini, occurring in seven hauls, Oscillatoria tenuis Agardh, 

 taken once, Peridinium tabulatum Ehrenberg, taken twice, and 

 Chlamydomonas reticulata Gorosch, taken three times. The spe- 

 cies represented are rather few in number, and the work of examin- 

 ing the material may be aptly described as monotonous. In the dis- 

 cussion of the algae, the plankton forms are not discussed sepa- 

 rately, but are considered along with other species that do not 

 enter into the plankton. 



