Vaillant was inclined to take a different view, but with considerable diffidence, owing to his inability actually to trace an open duct. I believe Günther to be right on this point, as well as in his account of the suspension of the pectoral arch in Notacanthus, which I have been able to verify. Besides, Mr. W. S. Rowntree, who has great experience in these matters, has kindly examined at my request a well-preserved example of Halosauropsis macrochir, and informs me that "the air-bladder passes anteriorly into a tapering band of tissue which ends in a thread-like ligament attached to the stomach near its posterior end and in the mid-dorsal line—not to the oesophagus; no trace of an open communication could be found."
Fauna u. Flora d. Golf. v. Neap. ii. 1880.
Quart. Journ. Micr. Sci. xlv. 1902, p. 503.
Ann. Sci. Nat. (8), xiv. 1902, p. 197.
Ann. Mag. Nat. Hist. (7) x. 1902, p. 147.