II M'.IT- OF I H I CEPHALOPODA. 01 



A riMot le, lull the r\ | >l:i n:il i( >li which lie nnn- lli:in 



doubtful. Tlic M r\ opaipie :iml \er\ dark -kin of (he excluded 



Inter becomes thinner :m<l nearly 1 raii-bicjd. A I MM 

 period of developmem. if the skill is ;<irn awa\ .-Mill tin- viiellilie 

 >:ick deiached. one can i nt rod nee t o 1 he world . as I have often 

 done, tin- \oiiiiLi Sepia. I* swims iniiiiedia! e|\ . and rhai 

 color \vii h i lie invriii'st (Mcilit \ . 



Tin- rolorntinn of the Sc| i:i- >c\ cr:il <-cn1 iiin-l r-< in leu- h [fi 

 innl'f v:iri:illr ih.-ili licit of tin- :nlillls. r l'hr /rln':i-likr ll:ick 



I>MII<|S .-ire not seen, luit i lie lit'iM-f.-il iin! changes instantly iVom 

 ^r:iv to \\ iiit'-liroNvn. to vio icni. The yonn^ Scpins >ink 



into the sand, only showing :i pnn ol' llu- Icick nnd ihc hcnd : 

 tlic\ swim lik- :!)< :idnl s. 1m; MSCCIM! :ind descend more fre- 

 quently. 



The eye of the Sepi:i tins :i very sn-Mii^e :ip|)e;ir;inee ; the d:irk 

 pii|>il I'epresentino- e\:icil\ ;i w. \\ is t'urnislu-rl \vith:in upper 

 lid. colored by ehronuttophores. ;md :i narrower, \vhiiish under 

 lid; I lii-re is :dso a \cr\ distinct p:dpelr;il sinus. 



In the I'oulpe (Oelopns) ilu> ))iii)il is t rnnsvei-se ;ind ronn<le(l 

 :it its exiivniities. I have never seen it change its lorni. A 

 the Calamaries. 1 ha\c not been able to study their eye liviiiir. 

 on acconni of the extreme mobili.y of these animals. 



The >ea-water des; im-d lor respiration enters the cephalic 

 extremity of the branchial sack, and leaves by the siphon. The 

 al ernate movements of ihe openings of the sack and siphon can 

 be readily seen. 



The branchial sack in a number of adnb Sepias was dilated 

 from seventy to seventy-two .imesa minute, but in the yonim. 

 about an inch lonu'. the inspirations reached 140 in a miim:e. 

 This result surprised me: it confirms, for animals of variable 

 :eiiip ( .r:i!iire. the law e>;a bli>hcd lor IIOM- of fixed tempera! lire. 

 the number of inspirai ioii> i> in inverse Mie a-v. 



The Poiilpe respires more slowly: I only coiiiiied '. Inny-ei^ht to 

 forty inspirations in a minute in ihe only individual which I 

 have examined, the si/e of which wa> inl'rrior to that of nio-t of 

 the adult Sepias. Tin- dili'ei'eiice i- due. perhaps to ;he much 

 larger >i/e of the branchial --aek of the Poulpc. which permi 

 to introduce a; one time a more considerable qiiantitv of water 

 than the Sepia. 



