NOMENCLATURE OF " MICROSCOPIC OBJECTS ' ETC. 133 



species. We have here a very characteristic example of 

 that undue multiplication of species to which Ehrenberg 

 has been so prone. 



References to the Memoir. Modern Nomenclature. 



Plate I. 

 f. 7,9. Grammatophora tceniceformis (p. 17) . . . Grammatophora marina, Lyng. 



According to Kiitzing, Diatoma tceniceform^e, latruncula- 

 rium (Agardh), brachygonium (Carm.), Bacillaria Cleopa- 

 tra (Ehr.), B. adriatica, B. Meneghina (Lobarewsky) , and 

 Grammatophora oceanica are all varieties of this species ; 

 and I doubt the distinctness of macilenta (Smith) and some 

 others. 



fig. 10. ? 



11. Striatella arcuata, var. (p. 18) .. Rkabdonema arcuata, var. 



12. Fragillaria (p. 18) ... ( Probabl ? a thick variet ? of Fra ~ 



I gillaria capuana (Desm.). 



13. Gomphonema geminatum? (p. 18)1 x> i-h H u+f i 

 14. (p. 18) J 



1 5. Navicula (p. 20) Navicula didyma (Kiitz. ). 



16. (p. 20) 



17. (p. 20) 



18. (p. 20) 



19. (p.20) 



20. sigma Pleurosigma (species uncertain). 



21. (p. 20) 



Plate II. 



f.22. Surirella (p. 20) 



Plate I. 



f. 23. Cocconeis (p. 20) Navicula. 



24. (p. 20) Navicula. 



Plate II. 



f. 25. Cocconema (p. 21 ) Cocconema, or Cymbidum. 



It is impossible to distinguish isolated frustules of these 

 two genera, the chief distinction being that the one is 

 supported on a peduncle, whilst the other is free. 



f. 26. Campylodiscus (p. 51 ) Campy lodiscus (undescribed). 



Foraminifera [Recent) . 



f. 27. Bosalina globularis, D'Orb., orl Young individual of Planor- 

 Rotalia stigma, Ehr. (pp. 38-43) J b'ulina mediterranensis. 



All uncertain species. 



