THE ANNALS 



AND 



MAGAZINE OF iNATURAL HISTORY, 



[SECOND SERIES.] 



•' per litora spargite museum, 



Naiades, et circiim vitreos considite fontes : 

 Pollice virgineo teneros hic carpite flores : 

 Floribus et pictum, divae, replete canistrum. 

 At vos, o Nymphae Craterides, ite sub undas ; 

 Ite, recurvato variata corallia trunco 

 Vellite muscosis e rupibus, et mihi conchas 

 Ferte, Deae pelagi, et pingui conchylia succo." 



N.Parthenii Giannettasii Eel. 1. 



No. 55. JULY 1852. 



I. — On the Nervous System 0/ Ommastreplies todarus. 

 By Albany Hancock. 



[With two Plates.] 



1 HE Cephalopods are undoubtedly the most highly organized 

 of all the Mollusca ; their external organs, however, are of so 

 abnormal a character, that any attempt to trace their homologies 

 in the lower groups of that subkingdom would at first sight ap- 

 pear almost hopeless. Notwithstanding, numerous efforts have 

 been made with that view by able naturalists ; but apparently 

 without much success, for our knowledge on this subject still 

 remains in a most unsatisfactory state. 



For the purpose of elucidating this difficult problem, I have 

 recently dissected with much care the nervous system of Omma- 

 strephes todarus — the Loligo sagittata of English authors, and 

 now propose to give a detailed description of it, refraining at 

 present from any attempt to arrive at just conclusions respecting 

 the nature and signification of the organs of these active and 

 voracious animals*. 



* Before making this attempt, it seems desirable to make a close exami- 

 nation of the anatomy of the neighbouring genera. 



Ann. ^ Mag. N. Hist. Ser. 2. Vol. x. 1 



