42 



MUSSEL Fauna of maumee river. 



parts of the Maumee. It is therefore probable that they represent 

 the result of migrations by way of the Wabash and Erie Canal. One 

 example was found in the St. Marys Eiver and four in the Maumee 

 in the vicinity of Antwerp, Ohio ; a few dead valves were occasionally 

 seen, but not more than two or three at the most. None were found 

 below the point just mentioned. In the feeder canal, where condi- 

 tions were particularly favorable for a study of the fauna, four exam- 

 ples were found, and two fine valves, not mates, were obtained in the 

 mouth of the St. Joseph. The shells found in the feeder canal Y^^ere 

 of an elegant compressed form with numerous triangular tubercles 

 on the anterior portion, and represent the subspecies strigillatub 

 B. H. Wright, which is considerably more attractive than the type 

 form. They are rather dark in color, with green triangles, as is 

 usual, and fine capillary rays. One example contained two Atax. 

 This attractive species is not well suited to button making on account 

 of its form and the fact that the nacre is frequently diseased ; hence 

 it is practically unknown to the trade. 



7. Quadrida undulata {BsiYnes) . Three-ridge, blue-point. With the 

 exception of Lampsilis ligamentinus^ Quadrula undulata is the most 

 abundant species of mussels in the Maumee Basin. All the undulate 

 mussels found were referred to this species except those at Put-in Bay, 

 Lake Erie. Notwithstanding the statement made in nearly all the 

 literature at hand that "the two species « are perfectly distinct and 

 there is no need of confusing them," many examples were found that 

 were hard to place. Different authors do not agree perfectly as to 

 the differences between these species and, generally speaking, the 

 characteristics given are rather vaguely expressed, a fault not due to 

 the carelessness of describers but to the nature of the case. All de- 

 scriptions seem to agree in stating that the umbones are more inflated 

 in plicata^ but we find this feature as variable as any other. In the 

 large collection of shells of the Bureau of Fisheries belonging to 

 these two types we have many intermediate forms and several series 

 exhibiting almost perfect transition from one species to the other. 



This species, as we have it, is exceedingly variable, so much so that 

 in looking over the entire summer's collection it was possible to give 

 the locality of a number of shells simply from their appearance. 



Q. undulata was found to be fairly common along the river where 

 there were any shells at all, and on account of its abundance only a 

 small proportion of the shells seen were retained. Fourteen were 

 obtained at the riffles in the St. Marys, where it was fairly common. 

 In the St. Joseph River at Robinson Park and in the feeder canal it 

 was abundant and attained large size; 10 examples were obtained 

 from the St. Joseph and 23 were taken of the large number seen in 

 the feeder canal. It also throve in the reservoir of the feeder canal. 



« Q. undulata and Q. pUcata. 



