BATHYPELAGIC SQUID BATHYTEUTHIS 91 



clubs of the Bathyteuthidae weakly resemble those of the Promacho- 

 teuthidae, INIastigoteuthidae, or Joubiniteuthidae by having many 

 rows of minute suckers, but the bathyteuthid clubs are very short and 

 they have few^er sucker rows; in this respect they resemble the 

 Cte nopte ry gi dae . 



The connectives of the buccal membrane attach to the oral surface 

 of the base of each arm at either the dorsal or ventral edge. The con- 

 nectives attach dorsally to anns I and II and ventrally to arms III 

 in all oegopsids. {Eiwploteuthh duhki Adam, 1960, is the only known 

 exception; the connectives attach dorsally to all four pairs of arms.) 

 The connectives to arms IV may attach dorsally or ventrally. Tlie 

 order of attachment is a constant feature within oegopsid families. 

 Furthermore, families that show relationships by other characters 

 also have the same order of attachment (e.g., Lycoteuthidae and En- 

 oploteuthidae ; Mastigoteuthidae, Chiroteuthidae, and Promachoteu- 

 thidae). The Bathyteuthidae have buccal connectives that attach 

 dorsally to the ventral arms. This character is shared with the 

 Enoploteuthidae, Lycoteuthidae Histioteuthidae, Psychroteuthidae, 

 Neoteuthidae, Architeuthidae, and Ommastrephidae. 



Most oegopsid families have a biserial arrangement of suckers or 

 hooks along the arms. The Enoploteuthidae and Octopoteuthidae, 

 which have mainly hooks, may have two to four rows of minute suckers 

 at the arm tips. Species of Gonatidae generally have two median rows 

 of hooks and two lateral rows of small suckers on the dorsal three 

 pairs of arms. At the arm tips the hooks may be replaced by suckers. 

 The ventral arms always have four rows of suckers. The tips of the 

 arms in Gonatopsis octopedatus have many rows of small suckers. The 

 Joubiniteuthidae have five to six rows of suckers along the dorsal 

 three pairs of arms and four rows along the ventral arms. The Ctenop- 

 terygidae have five to six in-egular rows. In the Bathyteuthidae the 

 suckers originate on the bases of tlie arms in a biserial arrangement, 

 then increase to three and four irregularly arranged rows. The number 

 of rows of suckers in tlie Joubiniteuthidae, Ctenopterygidae and 

 Bathyteuthidae is generally similar, but other characters weigh more 

 heavily to preclude a close relationship. Therefore, multiple rows of 

 suckers occur independently in a few families that are widely diverse 

 on the basis of more stable familial characters. 



The gladius in oegopsids should show relationships between higher 

 taxa, but no comprehensive study of oegopsid gladii has appeared in 

 the literature, and, other than the gross features, no taxonomically 

 important characters of the gladius have been delineated. In fact, in 

 many species the gladius remains undescribed. Still, it is possible to 

 find general similarities between gladii of some groups. Several fami- 

 lies have a long, thin rhachis, a reduced or absent free vane, and a 



321-534 O— 69 7 



