620 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxv. 



In each genus an abundance of material was at hand, and when 

 characters could not be fully made out in one specimen others were 

 used until a degree of certainty as to limits of bones and indistinct 

 sutures was reached which would have been impossible with single 

 specimens. 



Among the mistakes tliat have been made in the osteology of the 

 group from time to time (most of which have been many times 

 repeated) are the following: 



Dr. Cope,^ besides speaking of the '^presence of the interclavicles 

 (which I find in all)," says "basis cranii simple; no tul>e." 



The former statement is treated elsewhere in this paper. As to the 

 latter, Ifacrorhamjyhosns has a double basis cranii with a well-developed 

 tube or myodorae. Both families of the Gasterosteoidea have the basis 

 cranii rudimentary in bone but completed in cartilage. Both families 

 of the Aulostomoidea have the basi-sphenoid l)ridging the anterior 

 edges of the prootics above the rectus muscles of the eye, but with no 

 tube in continuation. This character has not the value Dr. Cope 

 placed upon it, as Dr. Gill has shown. 



Dr. (iill, in his kej^ to the families of these fishes, '^ includes Gas- 

 terosteidie and Aulorhynchida? under the character ''pubic bones con- 

 nected with scapular arch.'' In AulorJiynehus the pubic bones, though 

 close behind, and slightly between the posterior part of the shoulder 

 girdle, are not attached nor even in contact. In Ga.sterosteu-^ a proc- 

 ess from the shoulder girdle overlies the pubic bones slightly, but the 

 integument and even the silvery pigment of the body is interposed 

 between them. The pelvic girdle is easilj^ movable, independent of 

 the shoulder girdle. In Eucalhi the pelvic does not nearly touch an}' 

 part of the shoulder girdle. 



Dr. GilP sa3^s that the "palatine bones are directly articulated 

 with the quadrate without the intervention of the pterygoids. In 

 Fistularta it appears so, as the suture between the quadrate and the 

 pterygoid whicn extends forward is difficult to make out. Prolonged 

 maceration, however, always separates the quadrate from the ptery- 

 goid. In a small specimen bending the bones in this region often 

 opens the suture. 



In Aulostoma the suture is conspicuous in the same place that it is 

 in Fistularia^ but there is no anterior element (palatine) apparent. 

 An examination of the cranium, however, will show that the palatines 

 have become ankylosed to each other and to the cranium at* each side 

 of the ethmoid. The pterygoid lies at each side of them ])ut slightly 

 attached. They hook over the maxillaries slightly as is typical. 



' Observations on the Hystematic Relations of Fishes, Proe. Anier. Asso. Adv. 

 Sci., 1871, p. 317. 

 "Proc. Acad. Nat. Sci. Phila., 1884, p. 156. 

 * Johnson's New Universal Cyclopedia, TIT, ]>. 801. 



