Note 404 — Chapter XV · CLASS GASTEROPODA (continued): OPISTHOBRANCHIATA AND PULMONATA
Reading edition
In deference to Bergh’s high authority, the position of a sub-order is here given to the Ascoglossa. It may be doubted whether that position will stand the test of further investigation, and whether the families concerned will not be added to the Cladohepatic Nudibranchs.