Ill 



KEPOKTS FROM THE INDIANA UNIVEKSITY P>10- 

 LOGICAL STATION AT AVINONA LAKE* 



(1. The Individuality of the Maternal and Paternal Chromo- 

 somes IN the Hybrid Between Fundulus IIetero- 



CLITUS AND MeNIDIA NoTATA. 

 W. J. MOEXKHAUS. 



[Abstract.] 

 In the hylirid l.rtw*"on F,ni<IiiUis Inirrnrlitus aiia Mnmiia untafa it is 

 possible to distinguish the chroinosoines that come from earh parent. 

 The chromosomc^s of FumJuhis hcta-oclitus are long and straight Avhlle 

 those of MrnMia nntuta are short and slightly enrved. This difference 

 thev maintain in the hybrids. They ean best be distinguished during the 

 anaphases. They can not be distinguished in the resting stage. During 

 the Hrst two <-leavages each kind of chromosome remains grouped biUit- 

 terallv upon the spindle. After the second cleavage they become mingled 

 npon the spindle, but the two kinds still retain their iudividuality and 

 can readily be identitied They have been thus traced to a late cleavage 

 stage, as far as was attempted. 



6. An Extra Pair of Appendages Modified for Copulatory 

 I'URPOSES IN Camisarus Viridis. 



W. J. MOENKHAUS. 



Among the crayfishes used for dissection in the laboratory we came 

 npon a specimen that had three pairs of abdominal appendages modi- 

 tied for copulatory purposes. This is the lirst time I have ever seen such 

 abnormality and. furthermore, have not been able to find mention ni 

 literature of a similar occurrence. I have, therefore, thought it worth 

 while to make a nole of it. 



The specimen belonged to the species viridis and was about three 

 inches in length. Unfortunately the specimen had been so much mu- 



^T^^^^nlnbuHmi's from the /oologicnl Laboratory of Indiana Iniver.ity un.ler the direc- 

 tion of C. 11. Eigenmann. No. 53. 



