’s RIJKS MUSEUM a AN NAT UURLIJKE HISTORLE — LEIDEN. 159 



1894. Sesarma impressa Ortmann. Zool. Jahrb. Syst., Bd. 7 p. 723 — 
Samoah. 
1895. Sesarma (Kpisesarma) frontalis de Man. Zool. Jahrb. Syst. Bd. 9 
p- 172 — Atjeh. 
1899. Sesarma (Sesarma) impressa Nobili. Ann. mus. civ, stor. nat. 
Genova, (2) t. 20 p. 507 — Mentawei Islands and Timor Kupang. 
1899. Sesarma (Sesarma) frontalis Nobili. Ann. mus. civ. stor. nat. 
Genova, (2) t. 20 p. 509 — Engano (off west coast of Sumatra). 
1902. Sesarma (Sesarma) impressa de Man. Abhandl. Senckenb. Gesellsch., 
Bd. 25 Heft 3 p. 527 — Ternate, Batjan, Halmaheira. 
1902. Sesarma impressa Schenkel. Verhandl. naturforsch. Gesellsch. Basel, 
Bd. 13 p. 546 — Kema (Celebes). 
1905. Sesarma impressa Lenz. Abhandl. Senckenb. Gesellsch., Bd. 27 
Heft 14 p. 370 — Zanzibar. 
Specimens in the Museum: 
1 o', Halmaheira, Kiikenthal coll. 1893—94 (examined by de Man 1902). 
1 Q, Halmaheira, Huetink coll. 1902. 
1 o', 3 Q, Soemalata (N. Celebes), E. E. W. Schroder coll. 
3 o', Kisser @i—-Gtinea); Schidler coll. 1897. 
1 Q, Nias, E. E. W. Schréder coll. 1908. 
The variation, shown by this species, in the proportion of the distance 
between the external orbital angles and the length of the carapace, in 
such a way, that sometimes the latter dimension exceeds the former, has 
been repeatedly discussed by de Man. He also was the first to recognize 
(1887) Ses. similis as synonymous with Ses. impressa and afterwards 
(1902) to show clearly, that Ses. frontalis has been founded on not yet 
fullgrown specimens of the present species. The large series of dimen- 
sions, taken from no less than 11 specimens by this author renders 
further measurements useless. |. cannot as yet make up my mind to unite 
Ses. intermedia de Haan from Japan with Ses. iimpressa, as has been done 
by de Man (1902), who regarded the Japanese form at most as a variety, 
distinguished by somewhat less expanded meropodites of the walking legs. 
53. Sesarma (Sesarma s.s.) indica UW. Milne-Edwards. 
1837. Sesarma indica H. Milne-Edwards. Hist. nat. Crust., t. 2 p. 74 — 
i Java. 
1853. Sesarma indica H. Milne-Edwards. Ann. Se. nat., (3) t. 20 p. 186 — 
Indian Seas. 
1883. Sesarma indica de Man. Notes Leyden Museum, v. 5 p. 166 — 
Sumatra. 
