6 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
Inspection of raw data gave no indications of differences between 
sizes or sexes of specimens, and analyses were not attempted. A 
minor cause of variation is related to loss and regrowth of palps. 
While many of the palps missing from the specimens may have been 
removed during collection and preservation, the occasional presence 
of unusually small palps, typically weakly segmented, suggests that 
natural loss and regrowth can occur. This could reflect varying 
environmental stresses, apart from any genetical differences. 
TaBLE 1.—Comparative data of Australasian and American specimens 
No. of segments of Intermediate telson L/B rostrum 
mandibular palp lobes 
Aust. Amer. Aust. Amer. Aust. Amer. 
Mean 2. 3558 2. 6777 1. 3559 1. 0220 1.1021 1. 3037 
n 104 90 118 91 59 44 
Range 1-3 1-3 0-3 1-2 0.88-1.26 1.10-1. 54 
Standard deviation 0. 473 0. 491 0. 612 0. 147 0. 0821 0.134 
SiS sal as 0. 201 0.183 0. 451 0.143 0. 0745 0. 103 
mean 
Probability of differences (t test) (0. 001 ((0. 001 (0. 001 
L carapace L/B cornea L eye 
L rostrum B cornea 
Aust. Amer. Aust. Amer. Aust. Amer. 
Mean 4.7746 4.1534 1. 2013 1. 3090 1. 3230 1. 4679 
n 59 44 55 41 54 42 
Range 4.0-6.0 3.50-5.0 1. 08-1.36 1.04-1.55 1.08-1.46 1.12-1.92 
Standard deviation 0. 442 0. 371 0. 0589 0.340 0. 0733 0. 283 
Slander demalien 0.0926 0. 0893 0. 0490 0. 260 0. 0554 0.193 
mean 
Probability of differences (t test) (0. 001 (0. 001 ((0. 001 
INTERMEDIATE LOBES OF TELSON.—Kemp (1913) noted that an 
Australian specimen had two lobes on each side but the then known 
Chilean specimens had single lobes. Schmitt (1940, p. 181) noted 
single lobes on Southern California specimens and suggested that these 
differences might be ‘‘of more significance than may seem justified at 
present.” 
In counting numbers of lobes, difficulties were encountered over two 
American and one Australian specimen. These possessed on each side 
one normal lobe and one very small lobe just lateral to it; the latter 
were regarded as vestigial and were not counted. In addition, one 
side of an American specimen had a malformed telson, and this was 
excluded from the count. 
