ANATOMY OF AN AUSTRALIAN LAND PLANARIAN. 89 
The Atrium genitale—The common atrium genitale, into which the male and 
female organs open, is rudimentary and scarcely, perhaps sometimes not at all, recog- 
nisable, so that at first sight the male and female openings appear to be separate 
although very close together. Careful examination, however, shows that there is 
really only a single external opening. 
I have endeavoured to represent the peculiar condition of the copulatory organs 
in figures 382 and 48. The actual appearances presented by these parts depend 
somewhat upon the state of contraction of the specimen under examination, but I 
think there can be little doubt as to the general correctness of the above account, 
which is based upon the examination of horizontal and transverse serial sections and 
upon careful dissection. 
