350 PROCEEDINGS OF THE ACADEMY OF [1895. 



Tentacuta quatuor, anterius sita. 

 '• depilans. 1. Laplysia. 



Syst. Nat. 10. p. 653. Tethys limacina. 



RoniL pise. 1. p. 520. Lepus marinus. 



Gesn. aquat. 475. Lepus marinus Rondeletii. 



Bohads. mar. 3. t. 1, 2, 3. Lernea graphice. 



Seb. mm. 3. t. 1,/. 8, 9. 



Habitat in M. Mediterraneo; sanie depilans tactu. 



(B. 51. J foetidissima ad nauseam usque." 



The description of the genus is implied for the species depilans, 

 and it is also said to be the Tethys limacina of the Tenth Edition. 1 

 The second reference is to the same figure of Rondelet formerly 

 cited for Tethys leporina. The third reference repeats the earlier 

 citation to Gesner, with the same mistake as to the page. The fourth 

 reference is to the excellent figure of Bohadsch's Lernea, represent- 

 ing unmistakably the Aplysia depilans of authors. The reference to 

 Seba is less happy, the figures being too ambiguous for certain 

 determination. It is perfectly evident that Linineus' generic char- 

 acters of Laplysia were derived from Bohadsch's work; and as the 

 best figures are from the same source, the traditional identification 

 of depilans is fully sustained. 



Summary. — From the foregoing facts it would appear that ( 1) 

 the generic name Tethys Linn. 1758, must replace Aplysia and 

 Laplysia Linn. 1767. And (2) as a substitute for TethysL>mn. 1767 

 not 1758, we will probably be compelled to adopt either one of the 

 new spellings of this name proposed in the early part of the century 

 or an entirely new generic term. 



1 We would not replace the specific name defiilanshy limacina, because the 

 latter was not recognizably defined in Linnpeus' earlier edition. 



