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A view of the inferior mass from within the body cavity reveals 

 no evidence of a conical arrangement but instead are seen very promi- 

 nently marked the transverse septa at regular intervals corresponding 

 to the lengths of the vertebrae. It will be noticed, however, that the 

 septa appear to cease very abruptly at a distance of two thirds of 

 a centimenter from the axis. A careful dissection of a well stained 

 specimen along this line brought to view the same conical arrange- 

 ment observed in the superior mass. The cones in the distal and 

 middle rows are quite perfectly developed but those of the proximal 

 row are very imperfectly formed being too closely apposed to the 

 spinal axis. The directions of the apices in these rows are exactly 

 opposite to those in the superior mass, that is the proximal row of 

 cones has its bases pointing anteriorly, whereas in the corresponding 

 row of the superior mass the apices pointed posteriorly. The cones 

 are much smaller, being scarcely half as large as the over-lying ones. 

 The superficial sides of the bases as well as a large part of the super- 

 ficial lateral area are inseparably united to the dense fascia, lining 

 the body cavity. The outer sides of the bases in the distal row are 

 reflected to form the transverse septa while the deeper sides of the 

 bases are firmly attached to the lower side of the outer half of 

 the transverse processes. The inner sides of these bases are continued 

 to form the lateral boundary of a cone in the adjacent row. The 

 attachments of the middle row are so similar to those of the same 

 row in the superior mass that I will not give them. The apices of 

 these two rows are connected with the interior part of the apices of 

 the cones following, by a ribbon-like tendon. 



In the row adjacent to the spinal axis, the deep sides of the 

 bases adhere to the hypapophyses of one vertebra and the apices are 

 inserted on the hypapophyses of the vertebra following, so that each 

 hypapophyses serves for the attachments of an apex and the deep 

 side of a base. From this brief description it can be readily seen that 

 the general plan of the cones is the same in both dorsal masses. 



In the majority of the Amphibians, the inferior dorsal mass is a 

 part of the stratum forming the transversalis abdominis, and 

 has received various names. Professor Humphry (Journ. of Anat. and 

 Phys. Vol. VI) in describing the great Japan salamander has called 

 it subvertebral rectus. Schmidt, Goddard and van der 

 Hoeven name it rectus trunci internus and Mi v art has desig- 

 nated it in the Menopoma retrahens costarum. In Amphiuma 

 the two masses are separated only partially by the transverse pro- 

 cesses and the passage of the nerves and blood vessels. The in- 



