. The anatomical record. Anatomy; Anatomy. iivi'Driivsis OK thA anuka 85 DISCUSSION Entoderm. My observations boar out the assertion <if('orning ('99) that entodenn does not enter into the development of the frog's hypophysis after the manner described by Kupffer ('94) and Valenti ('95). There is indeed a mass of cells, epithelial in appearance, in relation with the anterior end of the notochord in larvae of \{. pii)iens having a length of to 3 mm. I am not able to find evidence that this mass becomes incorporated into the hypophysial anlage. That this eiiithelium-like mass is com- para
. The anatomical record. Anatomy; Anatomy. iivi'Driivsis OK thA anuka 85 DISCUSSION Entoderm. My observations boar out the assertion <if('orning ('99) that entodenn does not enter into the development of the frog's hypophysis after the manner described by Kupffer ('94) and Valenti ('95). There is indeed a mass of cells, epithelial in appearance, in relation with the anterior end of the notochord in larvae of \{. pii)iens having a length of to 3 mm. I am not able to find evidence that this mass becomes incorporated into the hypophysial anlage. That this eiiithelium-like mass is com- parable with the 'protochordal plate' of other vertebrates, as suggesteti by Corning, ^Irs. Ciage, and more recently by Parker, seems to me not unlikely. ???^ifi::^v^^:B^ f. I. I; , ml. I. Fig. 18 Parntiiedian sagittal section of hyjiophysis of an adult frog (R. pipiens). Plane of section indicated by line A-B, figure 14. Nasal end is at the left, inf., infundibulurn; , pars ; , neural lobe; p. in*., pars intermedia; ant., I., anterior lobe proper, X 50. The pam (uhcralis. \ two-fokl origin for the hypoj)hysis of Ajnbylstoma has been recordeil iiy Kingsley and Tiling. These observers believe that the bilaterality involves the entire gland and that the two parts soon fuse. The bilaterality observed in the frog's hypophj-sis seems, in certain stages at least, to be con- fined to the anterior portion of the anlage and does not extend to its caudal tip. I have never seen convincing evidence that the two parts come together and fus in the frog. It is with some difficulty that the two parts may be traced to the bud-like lateral lobes which later form the pars Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bardeen, Charles Russell, 1871-1935, ed; Boyden, Edward A. (Edward Allen), 1
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