41a. SUCCINEA RETUSA MAGISTER Pils. 
Cited from Michigan by Pilsbry. I have not seen any 
specimens however from this state, which agree with the des- 
cription of this form. The unusually large specimens from 
Kast Saginaw mentioned in the (Nautilus VII, p. 120), are 
quite different. 
71b. SUCCINEA RETUSA DECAMPI Tryon. 
It seems probable that this will prove to be simply a color 
variety common to all the various forms of S. retusa. The 
typical decamp/, of which two specimens from the original lot 
collected by DeCamp are in my possession, are quite evidently 
immature and, barring the peculiar ashy-gray color, would be 
referred to the elongated form of re/wsa above mentioned. 
Similar specimens occur in Lenawee county, and others, not 
quite typical in color, from Sugar Island, St. Mary’s river. 
A more effuse form, similar in shape to fcoriensis, but quite 
typical in color, is of quite frequent occurrence and often 
attains considerable size, some examples measuring 14 a in 
length. 
72. SUCCINEA OBLIQUA Say. 
If, as stated by Binney, Say’s ovals and vb/igua are syno- 
nyms, this species should be known under the former name, 
if the rules of priority are to be enforced. 
SS. ovalis was described in 1817 and 5S. od/igua in 1824. 
The use of od/7gua was inaugurated arbitrarily by Dr. Amos 
Binney (Terr. Moll. II p. 64) in an ‘‘attempt to reconcile the 
differences” in the use of the names by retaining ova/7s for 
Gould’s species and applying to ‘‘ Mr. Say’s species his second 
name obliqua.” ‘This, of course, he had no right to do. 
Ovalis has priority for either one species or the other, and 
should be recognized. 
Although not as abundant as either retusa or avara this 
species has a general distribution in the lower peninsula. It 
has not yet been reported from the upper peninsula. Occa- 
sional specimens are very close to the eastern form known as 
tottenzana both in color and form. 
73, SUCCINEA AVARA Say. 
Very abundant and of general distribution. Lime Island 
in the St. Mary’s river is the most northern locality yet 
reported. 
73a. SUCCINEA AVARA ALBA Ck’ll. 
Occurs occasionally associated with the typical form. 
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