898 



RADIATION BIOLOGY 



of Pagenstecher. Finally, the author lists almost a dozen "late mal- 

 developments," namely, nervous system changes found in the postnatal 

 period. Among these are: virtual absence of corpus callosum (also found 

 by Grobman — see p. 897), jumbling and reduction of the hippocampus, 

 malformations of the ventricles. It is interesting that extraneural 

 damage could be obtained only with the highest doses and that even then 

 it was rare except in the thymus (cf. Kosaka). 



All morphological changes — immediate and delayed — reported for 

 irradiation during the period of the fetus have been summarized in 

 Table 13-8. 



Table 13-8. 



Morphological Changes Following Irradiation during the Period 



of the Fetus 



3. TIME OF PARTURITION 



There are a number of scattered reports in the literature to the effect 

 that irradiation during pregnancy causes a delay in parturition. Since 

 most of these statements are concerned with irradiation during the 

 period of the fetus, they will be examined in this section. In rabbits, a 

 delay of 17 hours to 2 days was found by Sebileau (1906a, b — three cases 

 out of seven), of 3-4 days by Niirnberger (1920 — three cases out of three), 

 and of 1-2 days by Lacassagne and Coutard (1923 — three cases out of 

 nine). In guinea pigs, one instance of slight delay is mentioned by von 

 Klot (1911) ; de Nobele and Lams (1925) record one case of 3 and one of 

 8 days delay; and Kosaka (1928c) states that dead fetuses may occasion- 

 ally be expelled after the expected time. The same is true in rats 

 irradiated in the third week of pregnancy (Kosaka, 1928b) where the 

 young may be stillborn 1-3 days late. 



