Lake Maxinkuckee, Physical and Biological Survey 71 



the first contained 9 of the mites, the second 4, the third 15, with 

 Atax eggs in the mantle and body, the fourth 12 Atax and nu- 

 merous eggs of the mite on the inner surface of the mantle, the 

 fifth 3 Atax with eggs and the sixth 7 Atax with eggs and egg 

 scars. No other parasites were noted. No pearls were found, 

 only a few irregular slugs. 



In 1906 some of the immense L. ventricosa of Yellow River 

 were planted in the lake near shore not far from the old ice office. 

 A few died shortly after planting but near the same place 2 years 

 later some of the mussels were found alive and apparently thriv- 

 ing. Two of the large females were killed and examined. Altho 

 this was at a time when this species is usually gravid, one of these 

 individuals was sterile, apparently having failed to become impreg- 

 nated. The influence of its residence in the lake was marked by a 

 dark stain which covered the exposed portion of the shell. The 

 other had a few eggs in the gills, and numerous marginal cysts 

 in the mantle. About 10 Atax among the gills, and numerous dis- 

 tomids on the outside surface of the mantle in the umbonal cavity. 



13. LAMPSILIS MULTIRADIATA (Lea) 



Not abundant in the lake; occasional shells are found along 

 shore, and now and then they are encountered in the piles of shells 

 where muskrats have been feeding. A few living examples were 

 found in the mussel bed near the mouth of Norris Inlet and a few 

 at Long Point bed. In all hardly a dozen living examples were 

 secured ; of 563 shells taken from a pile left by a muskrat at Long 

 Point in 1907, only 1 was of this species. This mussel, as it occurs 

 in the lake, is not nearly so attractive as river specimens, being 

 dwarfed and so deeply stained that the rays are inconspicuous, 

 being usually black or dull brown instead of green. 



This species was found in unusual abundance in the Tippecanoe 

 River at Delong, and a considerable number was observed spawn- 

 ing during the autumn of 1908. While spawning, this mussel is a 

 very conspicuous spectacle. It lies either on its back, or more 

 usually with the posterior end directly upward, and the showy 

 edges of the mantle, which are of a yellowish brown color, and 

 cross-barred with narrow lines which are continuous with the fine 

 rays of the epidermis, look a good deal like a small darter lying 

 on the bottom. Long waving pennant-like flaps, with a showy 

 black spot at the base of each are developed, and this portion of the 

 mussel is made still more conspicuous by reason of periodic violent 

 spasmodic contractions. 



