HALORAGEA. , 401 
2. GUNNERA. 
Gunnera, Linn. Mant. 16 ; Benth. et Hook. Gen. Plant. i. p. 676. 
About twelve herbaceous species, dispersed in South Africa, Abyssinia, Java, Tas- 
mania, New Zealand, Sandwich Islands, and America, from Mexico to Patagonia and 
Juan Fernandez. 
1. Gunnera (Pankea) insignis, Cirst. in Vidensk. Meddel. 1857, p. 189; 
L’Amér, Centr. t. 18. 
Costa Rica, Volcan Irazu (Grsted). 
2. Gunnera, sp. 
South Mexico, Tortula, Vera Cruz, on the margin of the water (Linden, 82). 
Hb. Kew. 
3. MYRIOPHYLLUM. 
Myriophyllum, Linn. Gen. Plant. n. 1066 ; Benth. et Hook. Gen. Plant. i, p. 676. 
Aquatic herbs. About fifteen species, generally dispersed, both in hot and cold 
regions. Most likely other species will be found in Mexico and Central America. 
1. Myriophyllum heterophyllum, Michx. Fl. Am.-Bor. ii. p. 191. 
CanaDa southward to—Norra Mexico, Ojo Caliente, Chihuahua (Thurber). 
. 4, CALLITRICHE. 
Callitriche, Linn. Gen. Plant. n. 13; Benth. et Hook. Gen. Plant. i. p. 676. 
Aquatic or amphibious herbs. About a dozen species, some of them having a very 
wide range. 
1. Callitriche asa-grei, Hegelm. Monogr. p. 54, t. 3. £9, t. 4. £1. 
Widely dispersed in Norra AmeRica—Sovutn Mexico (Schaffner). 
2. Callitriche deflexa, A. Br. ex Hegelm. Monogr. p. 58, t. 3. fig. 2, t. 4. fig. 4. 
Southern States of Nort AMERIca.—Souta Mexico, Orizaba (Bottert, 834).—Cuna ; 
Brazit. Hb. Kew. | 
The Mexican specimen is doubtful. 
3. Callitriche verna, Linn. pro parte, ex Hegelm. Monogr. p. 58, t. 3. fig. 10. 
- Widely dispersed in Norta America southward to—Mexico, San Luis Potosi (Schaff- 
ner).—CuiLi ; also in Europe and Asia. Hb. Kew. 
Order LIT. RHIZOPHORACEA. 
Rhizophoree, Benth. et Hook. Gen. Plant. 1. p. 677. 
Trees and shrubs. About fifty species, in seventeen genera; natives of tropical 
countries, chiefly on the muddy shores, | 
BIOL. CENT.-AMER., Bot. Vol. 1, June 1880. 3f 
