ZOOLOGY. 363 



cuttle-tisli, bur in the old it is a single tube ; (2) in nautilus the eye is a 

 simple cavity opening externally by a minute aperture, as is the ease in 

 the embryo cuttle ; (.■») in nautilus the auditory organs are close beneath 

 the eyes, and so they are in the embryonic cuttle, but in the mature 

 dibranchiates they have api)roximated on the ventral side; (1) in nau- 

 tilus the tentacular and labial processes are more or less llattened and 

 lie one within the other, and in analogous manner in the dibranchiates 

 the arms rise as broad Hat processes, one pair within the others. Mr. 

 Blake contends (with Valenciennes) that the ])roc(;sses (six or eight) 

 from which the tentacles originate in nautilus are honudogous witli the 

 arms of the cuttle-hshes, aiul that the tentacles are homologous with the 

 suckers. The aptychus-bearing "hood" of the nautilus may be homolo- 

 gous either with the anterior port of arms of the dibranchiates (the ar- 

 gonaut thereby secretes its shell) or Avith the "neck-plates" just behind 

 the eyes and in front of the "bone" of iScpia, or the generalized basis 

 of both ; but this the embryology of nautilus must determine. The shell 

 of nautilus it is tliought may be represented in the dibranchiates by 

 the shell of Spiniltr, the phragmacone of a Belemnite, and the macro of 

 a Sei)ia-bone. The ink-bag which is deviOoped late in the embryological 

 history of the cuttle-iishes does not exist at all in nautilus. 



THE OEPIIALOPODS OF EASTERN NORTU AMERICA.* 



In the earlier works upon the molhisks of the eastern coast of North 

 America only three or four si)ecies were rec()rde<l, and until within the 

 last few years that coast was supposed to have lew inhabitants rei)re- 

 senting that class. Since the institution of the labors of the Fish Com- 

 mission, however, a number of new forms have been made known, and 

 some of them represent new genera. Among the most noteworthy are 

 species of gigantic cuttle-flsh, of which quite a large number of speci- 

 mens have now been dis(!overed in various places on the Great Banks, 

 and around or near the island of Newfoundland. The following are 

 all the si)ecies that have been made known as inhabitants of the north- 

 eastern coast of the United States to the end of 1880. 



Decapods. 

 Architeuthis princeps Y. Eossia Ilyatti V. 



Harveyi V. subUvvis V. 



iStheiwteutkis meyaptera V. Sepiola leueoptera V. 



Ommastrephis illicebrosa (Les.) V. Logllo Fealei (Les.) V. 

 Taoniiis pavo (Les.) Steenstrup. pallida V. 



hyperboreus ISteenstrup. Farasira eatenulata (Fer.) Steeu- 



HisfioteutJiis CoUinsii V. strup. 



Callilcuthis reversa V. Heterofeutkis tenera V. 



* Veriill (A. E.). Synopsis of tlio Ccpli.ilopoda of the iiortliciisteru coast of America ; 

 liiicf Contributions to Zoology from the Museum- of Yale College. No. XLVi. With 

 plates XII to XVI. Am. Journ. Science, {'^), \ci\. xix, pj). 28l-il)."). Also, noliceof the 

 remarkable Marino Fauna occupying the outer lianks of the southern coast of New 

 England. Am Journ. Science, {'.i,) vol. xx, pjj. :J90-4U3, 



