47 313 



same in both species. Only on the high part of the body, anterior to the first 

 dorsal and the ventrals, do unpaired ossifications occur, a row of 5 scutes forming 

 an uninterrupted lieel along the median dorsal line, while another, but interrupted, 

 series, composed of 4 (exceptionally 5 or 3) median scutes, is found along the ven- 

 tral margin. The members of the dorsal row are more or less cruciform, their 

 longitudinal stems suturally united together, their transverse branches — except 

 that of the first — united to the uppermost members of each of the paired trans- 

 verse series. The scutes composing the latter are star-like, their branches mostly 

 joined together, thus forming a kind of meshwork; the ventral members meet 

 their fellows from the other side or are firmly united to the median unpaired ven- 

 tral scutes. In this way the whole forepart, anterior to the fins, is apparently 

 made immovable, forming a kind of "thorax". Of the transverse rows on each 

 side of the "thorax", 3 behind the pectoral are most regular; in front of the pect- 

 oral the clavicle (cl) enters between the dermal ossicles, and the arrangement ap- 

 pears less regular. The hindmost of the 3 regular series consists of 6 members, 

 the ventral of which is joined to the posterior median scute (No. IV); the upper 

 4 are not connected with the next row in front. This row contains 4 scutes, the 

 ventral of which is joined to the median scutes II and III. All 4 members are 

 connected with the 4 forming the next transverse row; the ventral scute of this 

 row meets its fellow from the opposite side and moreover joins the unpaired scute 

 No. II; the second upper one is connected with a branch of the clavicle. The next 

 transverse row just in front of the pectoral also contains 4 dermal scutes; the ven- 

 tral joins its fellow from the opposite side; between the uppermost and the second 

 upper enters the clavicle, combining through a separate process with each. No 

 more complete transverse series are to be found, the shoulder girdle forming the 

 greater part of the skeleton at the anterior border of the body; only ventral der- 

 mal scutes are present corresponding to the ventral members of the transverse 

 rows. The foremost pair always meet in the ventral median line, while behind 

 them is interposed, between the next pair, the foremost unpaired scute I. Compar- 

 ing several individuals some minor irregularities may be found in this region, 

 while the more complete transverse series always seem to be identical as to 

 arrangement and number. 



Behind the thorax, on the slender part of the body and on the tail, an ar- 

 rangement of the dermal scutes in vertical transverse rows is more or less pro- 

 nounced, but in accordance with the greater mobility of this part the connections 

 between the component members are partly dissolved, and no unpaired median 

 scutes are found nor any junction between the scutes of the opposite sides at the 

 margins of the bodj'. Apart from the higher, hump-like, part carrying the second 

 dorsal and the anal each transverse row is composed of 2 or 3 members, rows of 3 

 alternating — but not quit eregularly — with rows of 2. In some of the 3-membered 

 rows the members may be more firmly connected, in others only loosely or not at 

 all, and the rows do not always correspond on both sides; that is to say, the same 

 row which on the right side consists of 3 members may on the left only possess 



