320 Additional Note by DR. SHAW. 
The Hirudo crenata of Mr. Kirby fhould feem by his defcription 
to be extremely near allied to the Hirudo geometra of Linn. and per- 
haps may be the fame fpecies in a young ftate. 
Mr. Kirby's obfervation relative to thefe animals forming a dií- 
tin& genus from Hirudo is unqueftionably right, for in fact they 
are real Planariæ ; and even the fpecies defcribed in the Linnean 
Tranfaétions by the title of Hirudo viridis comes fo near to the 
Planaria punétata, viridis, and Helluo, that it may be doubted whe- 
ther it be really diftinct, or a variety. 
TAF 29. 
Exhibits the Hirudo crenata, in feveral different views, of its na- 
icm E vun. two magnified, 
2 0c XXE a 
ii 
