FLORA OF THE DISTRICT OF COLUMBIA. 251 



8. MIMULITS L. Monkey tlower. 



Leaves sessile; pedicels longer than the calyx 1. M. ringens . 



Leaves petioled; pedicels shorter than the calyx 2. M. alatus. 



1. Mimulus ringens L. 



Swamps and along streams; frequent. July-Aug. Eastern N. Amer. 



2. Mimulus alatus Soland. 



Swamps and along streams; frequent. July-Aug. Eastern U. S. 



Mazus japonicus (Thunb.) Kuntze, a small annual with blue flowers, native of 

 Asia, was collected in the Department of Agriculture grounds in 1895 and 1896. 



9. MECARDONIA Ruiz & Pav. 



1. Mecardonia acuminata (Walt.) Small. Water hyssop. 



Low ground along the Potomac; infrequent. July-Sept. Southeastern U. S. 

 (Herpestis nigrescens Benth.; Bacopa acuminata Robinson.) 



10. GRATIOLA L. Hedge hyssop. 



Capsule globose, as long as the pedicel; plants glabrous or nearly so. 



1. G. vlrginiana. 

 Capsule ovoid, much shorter than the pedicel; plants finely glandular-hairy. 

 Leaves lanceolate, mostly 2.5-5 cm. long; stems usually branched; capsule equaling 



or slightly longer than the sepals 2. G. neglecta. 



Leaves broadly ovate, mostly 1 cm. long or shorter; stems usually simple; capsule 

 shorter than the sepals 3. G. viscosa. 



1. Gratiola vlrginiana L. 



Wet soil; occasional. May. Southeastern U. S. and Mex. {G. sphaerocarpa Ell.) 



2. Gratiola neglecta Torr. 



Wet soil; occasional. May-June. Widely distributed in N. Amer. {G. virginiana 

 of authors.) 



G. aurea Muhl. has been reported from our region, but no specimens have been 

 seen by the writer. 



3. Gratiola viscosa Schwein. 



Swamps along the Eastern Branch and Hunting Creek. Aug.-Sept. Southeastern 



U.S. 



11. SOPHRONANTHE Benth. 



1. Sophronanthe pilosa (Michx.) Small. 



Dry or wet soil, north and east of Washington; occasional. July-Aug. South- 

 eastern U. S. {Gratiola pilosa Michx.) 



12. ILYSANTHES Raf. False pimpernel. 



Pedicels longer than the leaves; calyx lobes shorter than the capsule 1. I. dubia. 



Pedicels shorter than the leaves; calyx lobes as long as the capsule or longer. 



2. I. attenuata. 



1. Ilysanthes dubia (L.) Barnhart. 



Wet soil along the Potomac; rare. July-Aug. Eastern U. S. (/. gratioloidcs 

 Benth.) 



2. Ilysanthes attenuata (Muhl.) Small. 



Wet soil along the Potomac and Patuxent; frequent. July-Sept. Eastern N. 

 Amer. {I. gratioloides of Ward's Flora, in part.) 



13. MICRANTHEMTJM Michx. 



1. Micranthemum micranthemoides (Nutt.) Wettst. 



In mud along the Potomac and Hunting Creek. Sept. Southeastern U. S. {M. 

 nuttallii A. Gray.) 



