252 JOURNAL OF CONCHOI.OGY, VOL. II, NO. 8, OCTOBER, IQOS- 



rarely six or seven ; in addition to this, tlie two innermost teeth bear 

 two or three denticles on the inside. Towards the end of the rows 

 the teeth have only one or two denticles, and the outermost teeth are 

 quite smooth. 



This specimen suggests that C. cincta and C. atrotnarginata may 

 be varieties of one species. The Hving animal seems to have had 

 very much the coloration of C. cincta, but, as preserved, there is no 

 reason why it should not be referred to C. atromarginata. 



Platydoris Bergh. 

 This genus belongs to the group of Cryptobranchiate Dorids which 

 have hamate teeth, no labial armature, and usually tripinnate 

 branchi^. It is distinguished from the other genera by its peculiar 

 hard consistency, and the armature of the genitalia. The outermost 

 teeth are often serrulate. The animals are usually very flat, with 

 broad mantle margins, and in the tropics are very common under 

 stones in the littoral zone. Outside the tropics the genus is recorded 

 from the iVIediterranean, but the Doris planata k. & H. of the British 

 coasts appears to be a Geitodoris, not a Platydoris. PI. variolata 

 has been removed by Bergh to Anisodoris. The following list of 

 species is taken from Bergh's "System der Nudibr. Gasterop.," with 

 some additions and alterations. 



1. PI. argo L. 



2. PI. philippi Bergh. 



3. PL canariensis {D' Orl>ig7iy). 



4. PI. punctata {D' Orlngiiy). 



5. PI. angustipes i^MdrcJi). 



6. PI. arrogans Bergh. 



7. PI. brunnea Bergh. 



8. PI. eurychlamys Bergh. 



9. PI. formosa {A. 6^ H.). 



10. PI. eUioti {A. 6- B.). 



11. PI. striata (AWfZ^rr/). 



12. PI. inframaculata (^4^;rt'//c7/;/). 



13. PI. coriacea i^Abrahaiii). 



14. PI. speciosa (^Abrahai)i). 



15. PI. murrea {Abraha)ii). 



16. PI. scabra {Cuvier). 



17. PI. sordida {Qicoy &^ Gainiard). 



18. PI. vicina Bergh. 



19. PI. (?) variegata Bergh. 



20. PI. hepatica {Abraham). 



21. PI. tabulata (^Abrahai/i). 



22. PI. pulchra E/iot. 



