346 Class XXI. Order VIII. 



* MYRIOPHYLLUM TENELLUM. Slender Water Mill/oil, 



M. erectum, aphyllum ; bracteis ii,tegris, obtusis ; 

 petalis linearibus conduplicaiis et revolutis. 



Erect, leafless ; bractes entire, obtuse ; petals linear, 

 condu plicate and revolute. 



Stem simple, erect, four to twelve inches high, round, smooth, 

 leafless. Flowers alternate, sessile, with oblong-obovate, obtuse, 

 concave bractes, twice as long as the flower. Calyx leaves very 

 short, acute. Petals white, oblong-linear, obtuse, three times 

 as long as the calyx, doubled backward and afterward revolute. 

 Stamens in the upper flowers, erect, as long as the petals; an- 

 thers oblong. Germs in the lower flowers, four, adnate ; stig- 

 mas four, persistent, recurved, pubescent, becoming feathery. 

 Capsules four, growing together. In the edge of Fresh pond, 

 also at Tewksbury. It is sometimes quite out of water and is 

 then very small. July. Perennial. Root creeping. 



* MYRIOPHYLLUM PROCUMBENS. Dwarf Myriophyllum. 



M. caule procumbente ; foliis pinnatifidis, subsexfi- 

 dis ; floribus axillaribus, solitariis, sessilibus. 



Stem procumbent ; leaves pinnatifid, about six cleft ; 

 flowers axillary, solitary, sessile. 



Stem slender, round, flexuous, rooting, branched. Leaves al- 

 ternate, pinnatifid, with five or six narrow, fleshy segments ; the 

 lower ones sometimes linear. Flowers axillary, solitary, sessile. 

 Calyx segments four, oblong, concave. Anthers four, oblong. 

 Germs four, oblong, tapering, upward ; stigmas curving outward- 

 ly. July. 



This minute plant grows upon the mud about ponds, and was 

 first sent to me from Danvers by Dr. Nichols. A specimen 

 which Mr. Boott received from the herbarium of Michaux, 

 marked " M. scabratum" resembled this nearly, except in be- 

 ing somewhat larger. Mr. Nuttall's M. limosum is perhaps a va- 

 riety. 



