LITHODES PANAMENSIS. 51 
the peduncle together ; the acicle is armed with a small tooth on the external 
margin midway between the base and the tip. There is no trace of an acicle 
on the left antenna in the type specimen, which is the only one obtained. 
The last segment of the peduncle is nearly twice as long as the penultimate 
segment. The chelipeds are furnished with scattered tubercles, a few of 
which assume a spiny character. The left cheliped is rather slenderer 
than its fellow. The ambulatory legs are long and rather slender, their 
meri sparsely furnished above with tubercles, which tend to assume a spiny 
form on the anterior and posterior margins; at the distal end of the anterior 
margin of the meri there is a prominent spine-like tooth; the carpi and 
propodites are armed with teeth, as shown in the figure; the dactyli are 
equipped with four short spines (two superior and two lateral) near the 
proximal end. The abdominal segments (of the female) are roughened by 
low tubercles and dentate on their margins. The lateral teeth of the mar- 
ginal plates of the right side are drawn out into long spines, as shown in 
Fig. 1°, Plate X. The tergal plate of the second abdominal segment is com- 
pletely fused with the epimera, showing no trace of an intervening suture. 
The marginal (episternal ?) plates of this segment are bounded within by a 
distinct suture. 
Length of carapace, excluding rostrum, 79 mm.; rostrum, 14 mm.; 
breadth of carapace, 79.5 mm.; length of posterior pair of ambulatory 
legs, 193 mm. (merus, 58.5 mm.; carpus, 31 mm., propodite, 54 mm., dac- 
tylus, 53 mm.). 
Station 3384. 458 fathoms. 1 fem. 
Lithodes panamensis finds its nearest relatives in L. turritus Ortm.,* from 
Japan, and L. murrayi Hend.,t from Prince Edward Island in the Southern 
Ocean. 
Two more species of Lithodes were obtained, but they are represented by 
specimens too young to furnish specific characters. One of these immature 
forms very closely resembles young individuals of Lithodes agassizii Smith, such 
as are represented on Plate I., Fig. 2, of Bull. Mus. Comp. Zodl., Vol. X., 
No. 1, and probably belongs to the same or a closely allied species. It is 
represented by three individuals (the largest 14 mm. long) from Station 
3365, 1010 fathoms, Station 3407, 885 fathoms, and Station 3418, 660 
* Ortmann, Zoolog. Jahrb., Abth. f. Syst., VI. 320, Taf. XIT. Fig. 26, 1892. 
+ Henderson, Rep. Challenger Anomura, p. 43, Plate IV., 1888. 
