APPENDIX 



Since the foregoing paper was written the United States National 

 Museum has obtained specimens of Apsteinia asymmetrica by 

 exchange with Prof. Max Weber, of Amsterdam. 1 The author 

 wishes to express his cordial thanks to Prof. J. E. W. Ihle, of Amster- 

 dam, for arranging this exchange. 



The adult individuals of both solitary and aggregated forms are 

 so flabby and collapsed as to be difficult to study, but there is 

 among them a beautifully preserved embryo 2\ millimeters long. 

 As this embryo shows the muscles in essentially adult condition, 





UJ 

 U.4 



el.'' 



Fig. 140.— Apsteinia asymmetrica, an embryo 2§ mm. long, viewed from the right side. X 44 



DIAMETERS. 



it is used chiefly in the following description of the structure in the 

 solitary individual. 



% APSTEINIA ASYMMETRICA, solitary form. 



The body muscles (fig. 140) grade off behind into the cloacal 

 sphincters in such a way that there is no sharp distinction between 

 the two sets. Using the same notation as in Apsteinia punctata 



Note.— The lettering of the figures in this appendix is the same as in the main paper. See the 

 Explanation of Text Figures and Plates on p. 179. 



i Cat. No. 6733, U. S. N. M. (immature aggregated zooids from chain). Cat. No. 6734, U. S. N. M. (soli- 

 tary and aggregated forms). Cat. No. 6735, U. S. N. M. (embryo), 1 specimen. 



183 



