96 VETERINAHY STATE BOARD 



membrane and presents at its middle the pyramidal body which 

 corresponds to the frog. Its base terminates in two lateral masses, 

 the bulbs of the plantar cushion. Its summit attaches to the plantar 

 surface of the os pedis and on each side it is attached to the lateral 

 cartilages. In structure, it is composed of fibrous, elastic and adi- 

 pose tissue, and contains vessels and nerves. 



Describe the coronary cushion. 



The coronary cushion is the matrix of the wall of the hoof. It 

 is lodged in a cavity at the upper border of this horny case. Its 

 inferior border is separated from the upper extremity of the lamina 

 by a white ring. Its superior border is limited by the perioplic ring. 

 The extremities are narrow and end in the velvety tissue of the 

 plantar cushion. In structure it is a modified skin made up of a 

 fibrous framework. 



What is the keratogenous membrane? 



This is the secreting structure of the horny foot. It envelops 

 the extremity of the digit and is covered by the hoof. It consists 

 of the coronary cushion (see preceding question), velvety and 1am- 

 inal tissue. The velvety tissue covers the plantar surface of the os 

 pedis and plantar cushion. The laminal tissue consists of 500 to 600 

 leaves, on the front and sides of the os pedis, which dovetail with the 

 leaves on the inside of the hoof wall. 



Describe minutely the mode of connection of the hoof wall with the 

 pedal bone and state how the weight of the animal is sup- 

 ported by the hoof. 

 The OS pedis is covered on the front and side by the laminal tissue 

 (see preceding question). This tissue consists of five to six hundred 

 parallel leaves, running from above, downward. On the inner side 

 of the hoof wall, there are analogous leaves, keraphyllous tissue, 

 which dovetail with these. 



The weight of the body is supported by the hoof wall and bars 

 through the intimate union of the horny and sensitive laminae. The 

 sole of the foot is slightly convex upward, thus making an arch-like 

 support. The frog, through the medium of the plantar cushion and 

 lateral cartilages, receives a share of the weight and the wall the 

 balance. 



Ductless Glands 



Mention the ductless glands and state where they are located. 



Spleen, adrenals, pituitary gland, thjrroid and thymus. 

 The adrenals, two in number, lie on the under and inner side of 

 the kidneys, in front of the hilus. 



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