30 U.S. NATIONAL MUSEUM BULLETIN 2 82 



and tended to diffuse indistinctly into the general mottlings of the side. 

 The head became especially broadened, and apparently flattened. The 

 mouth appeared to have enlarged. Several muscle masses became 

 swollen: one was located on the back just anterior to the dorsal fin; 

 another on the top of the head and behind the eye was separated from 

 the swollen mass of the opposite side only by a median depression, and 

 continued indistinctly to below the eye, where it appeared as another 

 enlarged mass on the cheek; the lips and an area around the base of 

 the maxillary barbel were also swollen. The appearance of post- 

 spawning females was not learned, since they did not occupy nests. 



In a night collection of 99 specimens taken mostly from a Chara bed 

 on August 10, 1951, 44 were males, 55 were females. Twelve of the 

 males resembled nesting individuals. Three of the females lacked the 

 general diffusion of pigment and the swollen muscles that characterized 

 breeding males, but had large eggs; they possibly would still have 

 spawned that summer. No post-spawning females were collected; the 

 remaining 52 females were immature and contained tiny undeveloped 

 eggs. 



Reproduction in Noturus stigmosus. — In the Huron River 

 Michigan, reproduction in N. stigmosus seems to occur a little earlier 

 than in N. miurus, and more eggs are laid. The Museum of Zoology, 

 University of Michigan, has two egg masses that were collected 

 July 27, 1932, in which the embryos are well advanced in development. 

 Another lot collected July 27, 1952, was guarded by a male 90 mm. in 

 standard length; it contained 89 eggs. Still another lot taken the same 

 day consisted of an incomplete brood of 61 young; it was also guarded 

 by a male 90 mm. long. A male 67 mm. long, collected on July 19, 1953, 

 was guarding 141 eggs. 



One of the first two egg masses was reported to have come from 

 gravel under a stone. The others came from cans which had fairly large 

 openings. It is likely that any small cavity of about the size of a 

 Number-2 can or larger with a large open end may serve as a nest. 

 Other adults were found in assorted cans, milk bottles, a coffee can, 

 and sunken boxes. As in N. miurus, occupied cans were free of detritus. 

 The nest-guarding male had the same features: broadening and 

 apparent flattening of the head; swellings of the lips, cheeks, back of 

 head, and predorsal region; and the general diffusion of pigments from 

 the constrasting or sharp markings of younger individuals, that are also 

 characteristic of brooding males of miurus. 



Early Development 



Four sac fry from a brood of Noturus miurus that was hatched the 

 night of August 10, 1951, were preserved the afternoon of August 14, 

 1951, and were stained with alizarin red S to determine ossified 



