188 NARRATIVE OF THE EXPEDITION. 



Mississippi and "Wisconsin valleys, was renewed in tHe descent of 

 the Fox River, particularly in the section of it below Winnebago 

 Lake. Shrunk to its lowest summer level, its shores disclosed 

 almost innumerable species of unios, many of which had been 

 manifestly dragged to the shores and opened by the musk-rat, 

 thus serving to give hints for finding the living species. Among 

 these, the U. obliqua, U. cornutus, U. ellipticus, U. carinatus, U. 

 Alatus, U. prselongus, and U. parvus, were conspicuous; the latter 

 of which, it is remarked by Mr. Barnes, is the smallest and most 

 beautiful of all the genus yet discovered in America.* In the 

 duplicates, from this part of the Fox River, transmitted to Mr. 

 Isaac Lea, of Philadelphia, he found a species with green-rayed 

 beaks, on a yellow surface and iridescent nacre, having a peculiar 

 structure, which he did me the honor to name after me.f The 

 description of Mr. Lea is as follows: "Unio Schoolcraftensis. 

 Shell subrotund, somewhat angular at posterior dorsal margin, 

 nearly equilateral, compressed, slightly tuberculate posteriorly to 

 umbonical slope. Substance of the shell rather thick ; beaks ele- 

 vated; ligament short; epidermis smooth yellow, with several 

 broad green rays ; teeth elevated, and cleft in the left valve, single, 

 and rising from a pit in the right; lateral teeth elevated, straight, 

 and lamellar; anterior cicatrices distinct, posterior cicatrices 

 confluent; dorsal cicatrices within the cavity of the shell on the 

 base of the cardinal tooth ; cavity of the beaks angular and deep; 

 nacre pearly white and iridescent. Diameter '7, length I'l, 

 breadth 1'3 inches." 



The next morning (20th), a heavy fog in the Fox Valley de- 

 tained us in our encampment till 7 o'clock. Six miles brought 

 us to another rapid, called the Little Kakala, which, however, 

 opposes no obstacle to the descent of canoes. At this spot, which 

 is the apparent western terminus of the Bay settlement, we found 

 a party of U. S. soldiers, from Fort Howard, engaged in digging 

 the foundations for a saw-mill. Our appearance must have been 

 somewhat rusty at this time, from our deficiences in the tonsorial 

 and sempstrescal way, for these sons of Mars did not recognize 

 their superior officers in Capt. Douglass and Lt. Mackay ; glibly 



* Amer. Journ. Science, vol. vi. pp. 120, 259, &c. 



•j- Transactions of tlie American Philosophical Society, vol. v. p. 37 ; plate 3, fig, 9. 



