Ladies' Slipper, Cypripedium pubescens, or C. parvifiorum. Official only in the Eighth U. S. P. and in no other national standard. Deleted from the ninth U. S. P., but added to the National Formulary.

Cypripedium is a nervine possessing an action akin to that of valerian; but it is less efficient. It is effective in functional hyperasthesias in 10- to 30-minim doses fl. In hysterical and irritable states it may promote sleep. Cerebral hyperemia is its indication, and conditions incident thereto are more or less amenable to its influence. It is a mildly-acting and not very effective agent; but it sometimes serves well in treating children and delicate women.