652 REPORT— 1902. 



The temporal touches the jugal in Hylohates miilleri, and thus shuts off the 

 parietal, ■which also touches the jugals from the sphenoid. 



The same arrangement almost takes place in Tarsius spectrum. 



The Cynomolgus, mentioned above as not having a parieto-sphenoidal suture, 

 has two small Wormian bones in the naso-frontal fissure. In the Homo above 

 alluded to the temporo-frontal suture is 20 mm. long, and the sphcnoido-frontal 

 11 mm. There are Wormian bones in the lambdoidal suture. 



There are Wormian bones in the naso-frontal suture of the leucoprymnus 

 referred to above, where the premaxillary bones almost reach the frontals. 



The parietal and sphenoid touch the jugal in Plapale jacchus and some other 

 American monkeys. 



This arrangement arises from the forward extension of tlie pariotal, excluding 

 the frontal from the sphenoid, and then the forward extension of the temporal 

 may exclude both frontal and parietal from the sphenoid. 



9, Notes on the Habits of the Onujyhididce {Polychceta) and on the Internal 

 Structures with which they Fortify their Homes. By Arnold T. 

 Watson, F.L.S. 



The Onuphididse are closely allied to the Eunicidfe, from which they are dis- 

 tinguished, amongst other things, by their always dwelling in deep water, whilst 

 the Eunicidje are often found between tide-marks. 



Observation of the British forms, Hi/alinwcia tubicola and OnitpJiis conchileffa, 

 while living in captivity, shows them to be errant worms, moving from place to 

 place and carrying their tubes with them. These tubes are open at both ends, 

 but the animal protects itself from the attack of enemies by constructing within, 

 at either end, membranous valves, on the principle of the valves in a vein, the 

 open ends of the pockets of which are directed outwards, so that by inrush of the 

 sea-water the valves are automatically closed on retreat of the inmate. 



In the quill-like, chitinous, transparent tube of liyalincecia the valves existing, 

 or which have existed, are indicated by the ornamental V-shaped or zig-zag 

 markings. 



The valves of OnupMs conclnlecju are much more delicate in structure, 

 but nevertheless are distinctly demonstrable in the internal membranous tube, on 

 removing with a weak acid the shelly covering which forms the scabbard-like 

 sheath. 



Very perfect valves of the kind described were also found in the tube of 

 Nothia pycnobranchiata, obtained by the ' Challenger ' Expedition from a depth of 

 2,225 fathoms. 



The habits of animals living at so great a depth can, of course, only be con- 

 jectured, but there is reason to think that, like the British species, these members 

 of the family may be errant worms. 



The paper was illustrated with lantern slides, and will be published in full by 

 the Liverpool Biological Society. 



10. On an Accelous Turhellarian inhabiting the common Heart Urchin. 



By R. T. Leiper. 



The turhellarian described in this paper was found by me in the accessory 

 canal of about 8 per cent, of the specimens of JEckinocarditim cordatum 

 occurring at Millport, N.B., several examples being usually present in the same 

 host. 



It is whitish and moderately translucent in appearance, leaf-like in shape, 

 obovate when contracted, lanceolate when extended, the blunt end being anterior. 



AVhen fully extended it measures in length 2*5 mm. ; in breadth, transversely, 

 0;6 mm. ; dorsiventrally, 0*2 mm. 



T)ie microscopical structur0 is (iescfibed ;n some d0tail, an interesting and 



