38 SOLENODON PARADOXUS. 



though on the ental face these Hnes cannot be seen. In Gymnura the sternal 

 cartihiges of but two ribs, the 8th and the 9th, are partly fused in this way. 

 The terminal cartilages of ribs 12, 13, 14, and 15, are bound by connective tissue 

 to the posterior rim of this large fused mass in Solcnodon paradoxus. The 

 extreme development of the sternal portion of the ril)s in Solcnodon is very 

 remarkable and apparently not found in other Insectivora. In a skeleton of 

 Ericulus setosus from Madagascar, however, a somewhat similar ossification 

 of the sternal portions of tlic ribs is present, but there is not the fusion of the 

 ventral elements in the posterior memliers. 



The first thirteen ribs have a double articulation: liy the capitellum to the 

 point of union of the vertebra with the vertebra next preceding; and l>\' the 

 tuberculum to the lateral surface of the prezygapophysis. The tuljerculum dis- 

 appears with the fourteenth rib and the articulation is at the anterior end of the 

 centrum of the respective vertebrae alone, not witli the centra of two ^•ertebrae. 



The sternum is of six pieces. The manubrium is roundly expanded an- 

 teriorly. It is not keeled, Init is slightly emarginate at the metlian extremity. 

 It thus resembles that of Erinaceus and Ericulus, and differs markedly from 

 that of Gymnura which is lozenge-shaped anteriorly, with a strong keel. The 

 three sternal pieces following the manubrium are quadrilateral, each slightly 

 longer than wide and narrower at the anterior entl. The fifth piece is evidently 

 a fusion of three elements, the last of which is the most reduced in width. The 

 flat narrow terminal element (xiphisternum) is articulated to its dorsal posterior 

 margin and bears a large oval cartilage distally. 



Compared with the sternum of Solenodon ciibamis as figinetl and described 

 by Peters, that of (S. paradoxus differs notaiily in possessing one less element. 

 There are seven sternal pieces in the former and t)vit six in tlie latter. This 

 difference seems clearly to be due to the comjilete fusion in S. paradoxus of what 

 in S. cubanus are the fifth and sixth pieces, so that in the former the penultimate 

 element of the sternum gives attachment to three sets of ribs instead of but two 

 as in the latter. The absolute length of the articulating segments of the sternum 

 is thus some 6 nmi. shorter in *$. paradoxus than in the Cuban species, notwith- 

 standing the greater general size of the former. A second difference is found 

 in the shape of the xiphioid process which in »S. paradoxus is simple, whereas in 

 S. cubanus it is represented as of two lateral portions fused anteriorly. 



The clavicles are large and slightly sigmoid in anterior aspect. They are 

 united by membrane to the antero-internal extremities of the manubrium and 

 curve, dorsal to the head of the humerus, to the dorsal edge of the tip of the 

 acromion. 



