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rings; as it covers part of the muscles of the pectoral fin I propose to call it the 

 "cover-plate" (c). The inferior lateral plate has the greater part on the ventral side, 

 where it forms a large junction with its fellow from the other side; it may be 

 termed the "jugular plate" (j). 



In a slit between the clavicle and Ihe "cover-plate" in front, and the lateral 

 and inferior lateral of the first ring behind, the basais or pterygials of the pectoral 

 fin are immovably fixed '". 



Closer inspection shows that the clavicular arch only contains the post- 

 temporal and the clavicle; the supraclavicle and the postclavicle are wanting. The 

 posllemporal is already mentioned under the skull. The clavicle (PI. Ill, figs. 1, 2, 6, 

 7 cl) has somewhat the form of a T; the anterior end of the horizontal branch is 

 connected through ligament to the posltemporal; besides this branch is immovably 

 fixed to the transverse processes of the 2 foremost vertebræ. The outer face of 

 the anterior part of the horizontal branch is smooth and excavated, forming the 

 interior wall of the tube leading to the gills; the hind part of the branch and the 

 uncovered part of the stem are sculptured in the same way as the dermal plates. 

 The lower end of the stem or vertical part is bifurcated, the outer branch (o) being 

 connected with the lateral part of the jugular plate, the inner (i) with the horizontal 

 part of the same. Through the passage thus produced a ventral portion of the lateral 

 muscles goes to the urohyal. 



The scapular skeleton is extremely weak; the cartilaginous part, preserved 

 to a small extent in all bony fishes, here forms the greater part of the whole; in 

 fact the ossifications appear so small in proportion to the cartilage, that the latter 

 has been mistaken by the previous authors for the whole scapular skeleton. 



The very small scapula (sc) has hitherto been quite overlooked; the cora- 

 coid (co) being much greater has not escaped attention but has been interpreted 

 as an "interclavicle". Parker wrongly supposed that it was composed of two 

 pieces, and hence he described 2 "intercla vieles"; Smitt observing better onlj' cor- 

 rected to one "interclavicle". Goodrich figures only a "coraco-scapular cartilage"; 

 the ossified coracoid is not represented in his figure, and the small scapular ossi- 

 fication is given as the first of his "5 radiais" (i. e. pterygials). 



The scapular foramen, present in other Teleosteans, here forms part of the 

 large opening between the clavicle and the scapular arch; just in front of the sca- 

 pular ossification pass the same nerves and blood-vessels which otherwise go through 

 the foramen scapulare. 



The 4 basais or pterygials (ba) are of peculiar shape. Their middle part 

 is a narrow stalk, basally and distally they are laterally compressed and broad; 

 so far their form might easily be derived from that found in Fistiilaria and Aulo- 

 stonia. But in the Lophobranch the distal part is on both sides provided with 2 or 

 3 thin processes, which at their end are flattened out into more or less irregular 

 plates. The latter lean against the dermal skeleton; those of the inner face are 



