Necturus Nest and Larvae 1 7 



vious effects of the radioactive tags. Prior to preservation the animal was 

 quite active and appeared healthy. Dissection revealed that the upper and 

 lower sections of the. digestive tract were empty, indicating that the 

 animal had not eaten recently. The liver appeared normal (compared 

 with other preserved specimens of similar size). The gall bladder was 

 filled with bile. Although no fat was evident the animal was not 

 emaciated. There was no indication of damage or irritation to muscle and 

 skin tissue from the tags. 



Thirty-two of the 35 egg capsules found were empty, but three were in 

 the process of hatching and the larvae appeared within one hour. 

 Although we netted for approximately 5 m around the nest, only four ad- 

 ditional larvae were collected, all within one meter of the nest site. Large 

 rocks and gravel reduced netting efficiency. 



Hatchlings (Fig. 1). — The mean total length of seven newly hatched 

 larvae is 22.8 mm (Table 1). The rounded head is totally unlike the 

 squared, elongate head of the adult and ranged from 3.5 to 3.7 mm (x = 

 3.5) long and 3.0 to 3.1 mm (x = 3.0) wide. The eyes are dark and appear 

 to be well formed. The forelegs are well developed, 2.0 to 2.2 mm long, 

 with the three outermost toes complete and the inner toe budlike. The 

 hind legs average 1.5 mm in length, are poorly developed, and are ad- 

 pressed to the lower tail fin. The tail is finned dorsally and ventrally, with 

 the dorsal fin slightly higher than the ventral and barely present at the 

 tail tip. Tail width in the series ranges from 2.9 to 3.2 mm (x = 3.0). 

 Because of the yolk sac the lower body is approximately 25 percent wider 

 than the upper body. The head and dorsum are rather uniform light 

 brown, and the color extends onto the area of the tail musculature. A 

 dark line extends from the nostril through the eye to the gills. Behind 

 each eye and above the dark line is a white, apparently rough, patch, 

 equal to or slightly smaller than the eye. The dorsal melanophores stop 

 abruptly on the side along a line level with the front and rear legs. Scat- 

 tered melanophores are present on the gills, upper surfaces of the legs, 

 lower jaw, and ventrolateral margins of the head. Melanophore concen- 

 trations are greatest in the area of the tail musculature, making the tail 

 slightly darker than the head and truck. The ventral tail fin is unpig- 

 mented, while the dorsal tail fin is clear on the margin with melanophores 

 increasing in number toward the musculature. 



Post-hatchling larvae. — Color patterns were observed in 61 preserved N. 

 lewisi larvae from the Tar and Neuse drainages and in one live specimen 

 from the Neuse. Accurate description of some was difficult because of 

 varying degrees of fading. However, 48 percent of all specimens (N = 28) 

 between 21 and 41 mm SV have a distinct dark lateral stripe on each side, 

 and 37 percent have a light dorsum with the dark sides not well defined 



