’s RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. 279 
IX. — DIAGNOSES OF NEW SPECIES OF MACRUROUS DECA- 
POD CRUSTACEA FROM THE SIBOGA-EXPEDITION. 
BY Dr. J. G. DE MAN. 
Nematocarcinus tenuirostris Sp. Bate, var. sibogae n. 
Stat. 300. January 30, 1900. 10°48°.6 S., 123°237.1 E. 918 m. 
Bottom fine grey mud. 4 adult females, 3 of which are laden with eggs. 
In the typical Nemat. tenuirostris, as described by Spence Bate (Report 
Challenger Macrura) and Miss Rathbun (The Brachyura and Macrura of 
the Hawaiian Islands. Wash. 1906, p. 926, Pl. XXIII, fig. 6), the 
rostrum is from two-thirds to one-half as long as the rest of the cara- 
pace, projecting horizontally forwards, the upper margin is slightly con- 
vex and it bears 9—13 dorsal and 1 or 2 ventral teeth. In the adult 
specimens, collected by the ,Siboga” off the south coast of Rotti, the 
rostrum measures, however, somewhat more than two-thirds the length 
of the carapace proper and is more or less obliquely turned upward 
from the orbital margin to the tip; it is styliform, tapering, quite 
straight, not at all convex in front of the eyes and armed above with 
8—10 teeth, beneath with one and of the dorsal teeth 3 or-4 stand on 
the carapace, posterior to the orbital margin. Length 146 mm. 
Plesionika longipes A. M.-Edw., var. indica n. 
Pandalus longipes, A. Milne-Edwards, Recueil de Figures de Crustacés 
nouveaux ou peu connus, Avril 1883, Pl. 20. 
Stat. 254. December 10. 5° 40’ S., 132° 26  E. Near the Kei-islands. 
. 310m. Bottom fine, grey mud. 1 male and 8 ova-bearing females. 
When the figures in the quoted ,Recueil” are indeed correct and ac- 
curate, the specimens, collected by the ,Siboga”, differ-from the typical 
species that occurs in the West Indies, by the somewhat shorter rostrum, 
which is less strongly upturned and armed both dorsally and ventrally 
with a much smaller number of teeth,and by the Ist tooth of the upper 
margin being only planted at one-ninth to one-tenth the length of the 
carapace from the orbital margin: they are therefore regarded as a new 
variety. 
Rostrum sometimes almost one and a half as long as the carapace, 
sometimes the difference is smaller. Postrostral carina obtuse, rising 
rather suddenly from the middle of the carapace, rostrum at first some- 
what depressed, afterwards ascendant, the apex situated at the same level as 
ae Lee 
(31—X—1917) 
