496 CHARLES R. STOCKARD AND E. M. VICARI 



thyroids in the bulldog group. Figure 2 is from 1143 $ , and 

 shows follicles of irregular size and outline. The epithelial 

 walls consist of actively secreting high columnar cells, and 

 the colloid is soft. A large amount of interfollicular tissue 

 is present. The entire picture brings to mind the thyroid of 

 the bulldog. The animal supplying this thyroid, seen in plate 

 62 (fig. 1) (p. 331), is only slightly nearer the bulldog type 

 than 10559 which supplied the hound-like thyroid (fig. 1). 

 The overgrowth of skin and other distorted features are, 

 however, more extremely expressed in 1143 $ . The exagger- 

 ated amount of skin shown by a completely "stuffed" brother 

 is well illustrated in plate 62. 



Figure 3 (pi. 94) is one of the most striking pictures that 

 can be presented by the thyroid. It represents a section of 

 the gland from 11455, shown from life in plate 62 (fig, 2). 

 This dog is a brother to the animal just discussed, and both 

 were vigorous animals of 18 months when killed. No. 1145 $ 

 has a clearly expressed, but poorly typed bulldog head. The 

 thyroid section of this animal shows follicles that are medium 

 or very small in size. The follicular walls are folded and 

 irregular in outline and are not fully expanded. The follicular 

 epithelium is high columnar and extremely active. The cell 

 bodies are filled with granular cytoplasm, and the nuclei 

 lie far away from the follicular lumen. Wide borders of 

 confluent secretion droplets are seen around the periphery 

 of the follicles, and small masses of fresh light staining colloid 

 lie nearer the center. The thickness of the follicular walls 

 is most remarkable. This gland clearly illustrates a state 

 of extreme thyroid secretory activity, and the gland from 

 the brother (fig. 2) is not far below in this respect. 



PLATE 94 



EXPLANATION OF FIGURES 



Bassethound-English bulldog cross. Further illustrations of the variation in 

 thyroid histological pattern to be found among second generation hybrids. 



1 1055$. 3 1145 <?. 5 916 rf. 



2 1143 <?. 4 902$ 



