204 F. W. GAMBLE, B.SC. 



direction appears to be " right-handed." von Graff notes an interesting 

 "left-handed " variety. The germaria are large lateral oval sacs, placed 

 opposite the centre, and directed forwards. The spermotheca is 

 finger-shaped with muscular walls. It contains the granular secretion 

 of a large number of glands. 



Habitat. — On half decayed Laminaria and Ulva, Millport (v. Graff); 

 under stones between tide-marks, St. Andrews (Mcintosh, 45); among 

 decaying Ceramia, &c, Port Erin, Isle of Man (F. W. G.). 



Distribution. — Egedesminde, West Greenland (Levinsen), Faroe 

 Islands (Schmidt), Bergen (Jensen). 



Sub-family Acrorhynchin^. 



Proboscis at the anterior end provided with a sheath opening in front, with 

 muscular cone and four long retractors. Pharynx rosulate. Yolk- 

 glands reticular (v. Graff [53], p. 318). 



Genus 12. — Acrorhynchus, v. Graff. 



Acrorhynchinas with a common genital pore. Two germaria and elongate 

 testes. Vesicular seniinales and granulorum distinct, but enclosed in 

 a common muscular penial sheath. The copulatory organ transmits 

 both secretions (v. Graff, ' Monogr.,' p. 319). 



21. Acrorhynchus calbdonicus (Claparede). 



1861. Peostomum caledonicum, Claparkde. (35), 



Length 1 — 2 mm. Body bluntly pointed in front, gradually 

 widening behind, and rounded posteriorly. Colour, proboscis white, 

 the rest of the body greyish brown with light areas, indicating the 

 positions of the more bulky internal organs. Rhabdites very small, 

 numerous, evenly distributed. Proboscis well developed (for an 

 account of its structure see v. Graff, ' Monographie,' pp. 119 — 124). 

 Two very long retractor muscles extend from its base to the posterior 

 end of the body. Pharynx before the middle, with a marginal "seam." 

 According to von Graff, the base of the extended proboscis is enclosed 

 in a nervous commissure proceeding from the brain. Eyes two, 

 provided with a lens. The genital pore is placed just behind the centre. 



