Fic. 9. 
9a. 
Fie. 1. 
Fie. 2. 
iGo 
Fic. 4. 
ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 521 
Burrow of Cambarus carolinus Erichson, located in a swampy place in stiff yellow clay, 
at Listie, Somerset County. Opened by the writer Aug. 12, 1904. 
Diagram of disposition of piles of mud seen from above. 96. Section of hole along line 
A-D. 9c. Section of hole along line A~B-C. A. Open chimney. B. Closed 
chimney. D. Closed chimney, hole filled up a good distance below surface of ground. 
C. Open hole, without pile of mud, situated under the edge of a large fiat stone (s). 
wl, water level ; x, place where the crawfish (male, first form, 61 mm. long) was found. 
PLATE XULI. 
3urrow of Cambarus bartoni (Fabricius). Located in the sand and gravel of the dry 
bed of a small stream, Edgewood Park, Allegheny County. Opened by the writer, 
Oct. 10, 1903. mp, pile of mud, consisting of mud, sand, and gravel; s, large slab 
of stone, lying imbedded in sand and gravel ; wl, water level (the stream was dry for 
long stretches, only here and there pools of water were left); x, place where crawfish 
(female, 63.5 mm. long) was taken. 
Burrow of Cambarus monongalensis Ortmann, Located in yellow clay (mixed with 
humus), at a springy place on the bank of small stream, near Monongahela City, 
Washington County. Dug out by the writer, June 16, 1904. 
Diagram of burrow and chimneys, seen from above; 26, section of hole along line 
A-B_-C’; 2c, section of hole along line C-D-E. A, hole opening laterally, with 
one-sided pile of mud in front, keeping up the level of water; B and D, closed 
chimneys ; C, open, large, and regular chimney ; w/, water level ; st, stream ; 2, places 
where the old female (mother, 65 mm. long), and ten young (20.5 to 32.5 mm. long) 
were fouud. Water, in a weak flow, was running in at “and wasrunning out at A. 
Burrow of Cambarus monongalensis Ortmann. Located in yellow clay, at a springy 
place on the bank of a small stream, Edgewood Park, Allegheny County. Dug out 
by the writer, May 9, 1904. The burrow is of a type similar to the one figured in 
Fig. 2, but less complex. a, hole opening laterally, with one-sided pile of mud keep- 
ing up the level of the water ; b, closed chimney ; w/, water level ; st, stream ; x, place 
where the crawfish (female, 63 mm. long) was taken. 
Burrow of Cambarus monongalensis Ortmann. Located in black muck, at a springy 
and swampy place at the bottom of the upper part of Fern Hollow, Pittsburgh, Alle- 
gheny County, opened by the writer, Oct. 18,1903. Type of a hole in level ground, 
with the water near the surface. No adults and only four young were found in this 
hole, but possibly the hole had additional branches, which were not discovered, the 
high stage of the water and its icy coldness rendering investigation difficult. About 
1.50 m. from this hole another was opened, which contained a female C. diogenes. 
a, closed chimney ; 6, one-sided chimney in front of hole opening obliquely ; w/, water 
level ; x, places where young specimens (11.5 to 16,5 mm. long) were found. 
