124 



favorite of the manatee or sea-cow. Other species of this wide- 

 spread genus include C. aequorea in the Mediterranean, C. rotun- 

 data in the Red Sea, C. preauxiana and C. webbiana in the waters 

 adjoining the Canary Islands, C. griffithii in the Antarctic off 

 southern Australia, C. angustata in the southern Indian Ocean off 

 the coasts of western Australia, C. isoctifolia in the waters of the 

 Indo-Pacific Oceans, C. australis in the Bay of Bengal, C. asiatica 

 in the East China Sea around the Liu-kiu Islands, C. acaulis off the 

 coasts of eastern Africa, C. nodosa in the Mediterranean, the waters 

 adjacent to the Iberian Peninsula, and those off the coasts of 

 northern and western Africa, and C. scrrulata widely distributed in 

 tropical seas. 



The New York Botanical Garden. 



BOOK REVIEWS 

 A Manual of Aquatic Plants* 



George T. Hastings 



Water plants are notoriously difficult to determine by the vegeta- 

 tive characters. Botanists in the Torrey Club range find the Key 

 to Submerged and Surface-Floating Aquatics published by Miss 

 Mary Barrett in the pamphlet Three Keys to Wild Flowering 

 Plants helpful, but its range is very limited and the plants included 

 are only those indicated by the title. Dr. Fassett has written a com- 

 plete manual of the aquatic plants of the United States from Min- 

 nesota and Missouri east to the Gulf of St. Lawrence and Virginia. 

 An aquatic is described as a plant that "may under normal condi- 

 tions germinate and grow with at least its base in the water." For 

 some reason bog and salt marsh plants are not included in the book. 

 The general key in the first part of the book and the keys to species 

 in the second part are based chiefly on vegetative characters. With 

 the general key are sixteen plates to illustrate the terms used and 

 the habits of the plants of each family. The descriptive treatment, 

 besides keys to the species, has brief descriptions of each species 

 and, with few exceptions, illustrations to show the whole plant with 

 enlarged details where they help in identification. Fully half of the 



* A Manual of Aquatic Plants. Norman Fassett. McGraw-Hill Book Co. 

 1940. vii -1-382 pages. $4.00. 



