126 CEPHALOPODA. 



Cuvier, and subsequently more fully investigated by De 

 la Fresnaye, the title of whose paper*, " Sur la mobilite 

 des taches que Ton remarque sur la peau des Calmars 

 subule et sepiole (de Lamarck), et sur la coloration spon- 

 tanee dont les sepiaires paraissent susceptibles," will 

 speak for itself. He inferred that this characteristic 

 phenomenon was similar to that of the chameleon. All 

 Cuttlefishes are more or less phosphorescent. The 

 eyes have a microscopic property, and may almost serve 

 as magnifying-glasses. " China ink " or ' ' Indian ink " 

 was formerly supposed to be prepared from the fluid of 

 some kind of Cuttlefish ; but it has now been ascertained 

 that the base of this paint is soot from the smoke of 

 oil-lamps. "Sepia," however, has a more legitimate 

 origin. Cuvier used the colouring-matter of S. offici- 

 nalis to illustrate the plates in his famous ' Memoires/ 

 The odontophore of the Cephalopods somewhat re- 

 sembles that of the Pteropods (Woodward) . 



The derivation of the word ' ' cuttle " is given in the 

 f Imperial Dictionary ' as from the Saxon verb " cudele," 

 in Welsh "cuziaw," and in Armorican " cutaff" or 

 "cuddyo," all signifying the sense of withdrawing or 

 hiding ; hence our pet word " cuddle." 



This class is the Cryptodibranchiata of De Blainville. 



Order DIBEANCHIATA, Owen. 



BODY naked : gills 2. 



Mr. Hyatt (Mem. Bost. N. H. Soc. n. s. i. pt. 2. 

 p. 208) calls these the " polar " forms of the Pteropoda, 

 and observes that " the general aspect, the arrangement 



* Mem. Soc. Linn, du Calvados, 1824, pp. 73-84. 



