614 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 113 
30, 1958; Limbaugh, Chess, and Hambly; 3 specimens (2 ovigerous).— 
Coral at 20 to 40 feet; August 1958; Allison and Limbaugh; 2 speci- 
mens (1 ovigerous).—Kast side, reef flat, margin or ridge, 0-2 feet; 
September 14, 1958; Limbaugh and Chess; 2 specimens.—Northeast 
side, 50-60 feet; September 20, 1958; C. Limbaugh; 1 specimen. 
MEASUREMENTS: Carapace lengths to base of rostrum, 1.9-6.0 mm. ; 
of ovigerous females, 5.3-6.0 mm. 
Remarks: Specimens that appear to be males, from the form of the 
abdominal pleura and pleopods, have a maximum carapace length of 
5.2 mm., shorter than that of the smallest ovigerous female; all larger 
specimens are ovigerous. 
DistRIBuTION: Red Sea to Baja California. 
Family Hippolytidae 
Lysmata trisetacea (Heller) 
Hippolyte trisetacea Heller, 1861, p. 29. 
Hippolysmata paucidens Rathbun, 1906, p. 913, pl. 24, fig. 4. 
Lysmata paucidens Schmitt, 1939, p. 12. 
Lysmata trisetacea Holthuis, 1947, pp. 19, 65. 
Materiau: Northeast shore, rocks south of landing place; July 21, 
1938; Sta. 9; W. L. Schmitt; 28 males, 5 females (3 ovigerous).— 
East side, coral reef; August 9, 1958; Sta. W58-283; Reese, Baldwin, 
and Wintersteen; 1 male, 1 ovigerous female.—South shore, coral reef; 
August 11, 1958; Sta. W58-285; Reese, Limbaugh, Baldwin, and 
Wintersteen; 2 males.—East end, coral reef; August 15, 1958; Sta. 
W58-289; Reese, Baldwin, and Wintersteen; 5 males, 14 females (12 
ovigerous).—South shore, coral reef; August 19, 1958; Sta. W58-295; 
Reese, Baldwin, and Limbaugh; 3 males, 2 ovigerous females. 
MEASUREMENTS: Carapace lengths of males, 2.0-4.5 mm.; of 
females without eggs, 2.0-4.7 mm.; of ovigerous females, 3.5-6.2 mm. 
Total length of largest male, 17.5 mm.; of largest female, 22 mm. 
Remarks: Males with carapace lengths of 2.0 and 2.1 mm. usually 
have the appendix maxculina on the second pleopods ranging in size 
from a scarcely visible bud to slightly longer than the appendix 
interna; in mature males, it is nearly twice as long. There is, how- 
ever, a single male with a carapace length of 2.0 mm. in which the 
appendix masculina is nearly fully developed. Apparently the 
appendix masculina normally reaches its maximum size at a carapace 
length of 2.2 mm., for all but one male of that size and all larger 
ones have the appendix masculina fully developed. 
It is noteworthy that 34 of the 36 specimens with carapaces less 
than 3.5 mm. long are males. The two possible exceptions have 
carapaces only 2.0 mm. long and they might be juvenile males, in 
which the appendix masculina has not yet appeared, rather than 
