1910] ANIMAL PBODUOTK lit).''. 



Intrauterine absorption of ova, A. W. IfRB [Aunt. /.'"•.. fl (1017), No. t, 

 pp. 203-307, jigs. 7). Prom histological examination and <»t i»*-r ronstdfimtlons it 

 is concluded Chat the email dead enbiyat found among the H when u 



guinea pig's uterus La opened up are absorbed i>y the uterus and not aborted. 

 Similar embryos are found in sheep and rabblta 



The ovulation period in rats, J. A. Loiffl and J. F. <.»' ISWO I 



}.; (1916), No. in,.',, pp. 705, 796), — Bight} nonpregnant and imiauckllng female 

 rats Isolated from males were tilled at timed intervals during mi days alter 

 giving birth to a litter, and their ovaries and oviducts cat into serial sectlona 



The 15 individuals killed during tin- first few days after parturition were 



used to study the rate of progress of unfertilized eggs through the oviduct 



and the changes iii tie- corpora lutoa, bo that corrections could be made 

 time elapsed since ovulation in the ease of animals killed at longer periods. 

 Of the remaining 65 females, 34 revealed ova iii lie- oviducts and 1-4 showed 

 evidence of receut ovulation from the condition of the corpora hitea. i 

 animals fall into groups having the following average intervals between 

 parturition and the most recent ovulation: Eleven, •_'(>, 30.25, S&5, •"■". > 

 BO) s '.». and !''.i days. The 17 rats not presenting evidence of recent ovulation 

 were all killed between the periods enumerated, it is concluded that ovulation 

 occurs on the average every 10 days. 



Ovulation in mice, J. A. Long and II. 1'. Smith {Science, n. ser,, J) [1916), 

 No. ll't'i, PP- 796', 7. ( '7). — From the study of G2 female mice by the methods of 

 Long and Quisno (see above), it is concluded that the normal ovulation period 

 recurs at ahout 17.5 to IS days. 



The ovarian cycle in mice, H. P. Smith (Anat. Bee, // (1017), No. 6, pp. 

 .',07-',l<n. In continuation of the above work of Long and Smith, a special 

 study was made of the variability of the time of occurrence of the second posl 

 partuni ovulation in nonpregnant mice. 



Nine females killed from IS to 20.5 days after parturition showed eggs in 

 the oviduct. From data which the author presents as to tie- rat.- ol pr» 

 Of unfertilized eggs in the oviduct, it is computed that the time between this 

 ovulation and parturition varied from it;. 5 to 10 days, the average being just 

 short of 18 days. The average interval between this and the lirsi post partum 

 ovulation was therefore a few hours less than 17 days. lull oilier Individuals 

 killed from the eighteenth to the twentieth day ami in 4 on the tvventy-!ir>t and 

 twenty-second days no indication of recent ovulation was found. While some 

 of these might have ovulated if they had been permitted to live a short time 



longer, most of them undoubtedly skipped this oestrous period, one individual 

 killed on the ninth day showed ova thai it is estimated had been extruded 

 from the ovary ('>.:> .lavs after parturition. Sixteen oilier females killed from 

 6 to 17.5 days afterwards showed no indications of ovulation. 



Oestrus and ovulation in swine, C. \Y. COBNZR and A. B. AJtfSBAUOB (Anat. 

 Rec, 12 U017), No. .'. pp. 281 1 98).—- The preliminary report Of these investiga- 

 tions has already been noted (E. S. EL, .".7. p. 887) in some detail. 



The corpus luteum of pregnancy, as it is in swine, Q. \V. Oo&Nl <• {Carnegie 

 Inst. Washington Pub. 222 (1915), pp. 69-94, P*», 3).— In this Investigation the 

 ovaries of 128 pregnant sows were examined, the purpose being to provide an 

 account of Hie histology of the corpus luteum at different stages of pregnancy. 

 In the material studied, which was from a slaughterhouse, from 1 to 10 corpora 

 lutes were found in each ovary, the most common total for both ovaries being 8. 

 The most frequent Dumber of fetuses was G. 



The corpora lutea are from 8 to 10 mm. in diameter and are very prominent, 

 nearly all their bulk projecting from the surface of the ovary. The I 

 organ is a light pinkish gray which only changes to yellow in late Bti 



