120 



Gen. 11. Ammothea, Leach, 1815. 

 Syn. Achelia. Eodge. 



Slægtscharacter. Legemet kort og undersætsigt, med 

 tæt sammentrængte Sidefortsatser. Hovedsegmentet mas- 

 sivt, med utydelig Hals og qvadratisk Pandedel. Haleseg- 

 mentet ikke sondret fra sidste Kropssegment, smalt cylin- 

 driskt, horizontalt. Øiekmulen nær Forkanten af Hoved- 

 segmentet. stærkt ophoiet med tydelige Lindser. Snabelen 

 skraat nedadrettet, indknebet ved Basis, tenformig. Sax- 

 lemmerne hos fuldt udviklede Individer meget smaa, 2-led- 

 dede, sidste Led kugleformigt. Folerne af middelmaadig 

 Længde. 8 — 9-leddede. De falske Fødder forholdsvis korte, 

 uden tydelig" Endeklo og med et meget ringe Antal af 

 saugtakkede Randtorner. Gangfodderne korte og robuste, 

 ofte piggede ; Laarleddet meget bredt, med det ydre Hjørne 

 mere eller mindre fremspringende; Tarsalleddet særdeles 

 lidet : Fodleddet kraftigt udviklet, mere eller mindre krum- 

 met og pigget i Inderkanten ; Endekloen stærk, Bikloerne 

 vel udviklede. Kjønsaabningerne hos Hannen beliggende 

 paa Spidsen af et stærkt Fremspring paa 2det Hofteled 

 af de 2 bagre Fodpar. 



Bemærkninger. Slægten Ammothea blev forst op- 

 stillet af Leach for en exotisk Art, hos hvem Saxlemmerne 

 endte med en liden, men tydeligt udviklet Chela. I 1864 

 undersogte den engelske Naturforsker, Hodge, en Del smaa 

 Pycnogonideer, hvoraf nogle ganske stemmede overens med 

 Leacb/s Slægt, medens andre, skjøndt forøvrigt temmelig 

 lige, mærkeligt skilte sig derved, at Saxlemmerne ganske 

 manglede Chela. Han saa heri en generisk Forskjel og 

 opstillede derfor for disse sidste Arter sin Slægt Achelia. 

 Denne Slægt blev ogsaa af andre Zoologer adopteret, ja 

 af Wilson endog stillet i en ganske anden Familie end 

 Slægten Ammothea. Forst Hoek har til fuld Evidens godt- 

 gjort, at begge Slægter horer sammen, idet Slægten Am- 

 mothea kun grunder sig paa yngre Exemplarer, medens 

 Slægten Achelia repræenterer de fuldt udviklede Individer. 

 En betydelig Reduction af de under begge Slægter opstil- 

 lede Arter bliver derfor ogsaa nødvendig. Foruden den 

 først opstillede Art, A. carolinensis, Leach, og de 2 neden- 

 for nærmere beskrevne Arter, hører herben en engelsk Art, 

 A. longipes, Hodge, en amerikansk. A. spinosa, Stimpson, 

 og 6 middelhavske Arter, nylig characteriserede af Dohrn 

 i hans Pycnogonideværk. 



38. Ammothea echinata. (Hodge). 



(PUXIIl. Fig. l, a— mi. 



Achelia echinata, Hodge, Ann. Mag. Nat. Hist. Vol. XIII, 



L864, p. Ila. Pl. XII, Fig. 7 — 10. 

 Ammothea brer/pes, Hodge, ibid. p. 114. Pl. XII, Fig. 



1-4 (juv.) 



Gen. 11. Ammothea. Leaeh. 1815. 

 Syn. Achelia, Hodge. 



Generic Characters. Body short and stout. with 

 closely crowded lateral processes. Cephalic segment 

 massive, with indistinct neck and square frontal part. 

 Caudal segment not separated from the last body-segment, 

 narrow cylindric, horizontal. Ocular tubercle near the 

 front of the cephalic segment, strongly protuberant, 

 with distinct lenses. Proboscis directed obliquely down- 

 wards, constricted at the base, fusiform. Chelifori, in 

 fully developed specimens . very small . 2-jointed . last 

 joint globular. Palpi of medium length, 8 — 9-jointed. 

 False legs relatively short. without distinct terminal claw 

 and with a very small number of serrated marginal spines. 

 Ambulatory legs short and robust, frequently spinous; 

 femoral joint very broad, with the outer corner more 

 or less projecting; tarsal joint particularly small; pro- 

 podal joint strongly developed, more or less curved and 

 spinous on the inner margin; terminal claw strong, aux- 

 iliary claws well developed. The sexual apertures, in the 

 male, situated at the point of a prominent projection on 

 the 2nd coxal joint of the 2 posterior pairs of legs. 



Remarks. The genus Ammothea w-as first established 

 by Leach for the adoption of an exotic species in which the 

 chelifori terminated in a small but distinetly developed chela. 

 In 1864 the English naturalist Hodge investigated a number 

 of small Pycnogonids, of which a few quite corresponded 

 to Leach's genus, while others, although otherwise pretty 

 similar. distinguished themselves notably by the chelifori 

 being quite awanting in chela. He regarded this as a 

 generic difference, and therefore established for those latter 

 species his genus Achelia. This genus was also adopted 

 by other zoologists. indeed even placed by Wilson in quite 

 another family than the genus Ammothea. Hoek was the 

 first who completely established that both genera belong 

 to each other. as the genus Ammothea is only based on 

 young specimens. while the genus- Achelia represents the 

 fully developed individuals. A considerable reduction in 

 the species ranked under both genera became therefore 

 necessary. Besides the first established species, A. carol- 

 inensis. Leach. and the 2 species more particularly de- 

 scribed hereafter, there also pertain to it. an English 

 species A. longipes, Hodge. an American one. A. spinosa, 

 Stimpson. and 6 Mediterranneau species. lately charac- 

 terized by Dohrn in his work on Pvcnogonida. 



38. Ammothea echinata. (Hodge). 



(Pl. XIII fig. 1, a— m). 



Achelia echinata, Hodge, Ann, Mag. Nat, Hist. Vol. XIII, 



1864, p. 115. Pl. XII. figs. 7 — 10. 

 Ammothea breripes. Hodge, ibid. p. 114. Pl. XII, figs. 



1—4 (juv.). 



