244 WM - s - MARSHALL AND C. T. VORHIES. 



Twenty-third, the larva had returned to its original case. Dur- 

 ing the six days of its greatest activity in building the larva had 

 constructed 36.5 mm. of new case, a daily average of 6.08 mm. 

 The daily average for the entire experiment was 2.25 mm. 



ZOOLOGICAL LABORATORY, UNIVERSITY OF WISCONSIN, 

 April, 1905. 



BIBLIOGRAPHY. 



1. Miall. 



'95 The Natural History of Aquatic Insects. London, 1895. 



2. Ostwald, W. 



'99 Experimental -Untersuchungen iiber den Kocherbau der Phryganeidenlarven. 

 Zeitschr. fur Naturwissschft., Bd. LXXIL, 1899, p. 49. 



3. Pictet. 



'34 Recherches pour servir a 1'histoire et 1' Anatomic des Phryganides. Geneve 

 1834. 



4. Reaumur. 



'38 Memoires pourservira 1'Histoire des Insectes. Amsterdam, 1738, Tome III. 

 5 Smee, Eliz. M. 



'64 The Caddis-worm and its Houses. The Intellectual Observer, 1864. 



