APPENDIX III 457 



twelve fathoms, where the shells were quite thickly covered with 

 the red algae. Seventeen specimens of both species of the red 

 chitons were obtained. The chitons are now placed in a separate 

 order, Amphineura, and represent the lowest type of the Mollusca. 

 They have a shell consisting normally of eight plates, hence the 

 name Polyplacophorq, the many-plate bearer, is applied to the 

 most important of the two suborders. 



A group of beautiful creatures when living, but very difficult to 

 preserve, are the Nudibranchs, or the naked-gilled Mollusca. The 

 large and handsome Dendronotus arborescens, with a row of tree- 

 like gills on each side of the back, and branching appendages on the 

 head, was obtained by Professor Packard in Henley Harbour, 

 at a depth of four fathoms. A species of Eolis is also reported 

 from the same harbour, and Coryphella diver sa from L'Anse au 

 Loup. A group of small shells, which are usually present in each 

 haul of the dredge, are known as Tectibranchs. They are re- 

 lated to the Nudibranchs, but have the gills covered, and usually 

 a shell varying considerably in form in the different families. 

 Cylichna alba, Retusa pertenuis, Philine lima, Scaphander punctos- 

 triata, and Diaphana hiemalis are the principal species. 



Each haul of the dredge brings in many other forms of animal 

 life besides Mollusca. The large brachiopod, Hypothyris psit- 

 tacea, is frequently obtained in from eight to fifteen fathoms, while 

 attached to the shells are a number of species of the beautiful 

 incrusting Polyzoa, or Bryozoa, and the minute Foraminifera. 



Among the interesting objects of the more open Arctic sea are 

 the little Pteropods, or wing shells. Packard reports great numbers 

 of the little Arctic pteropod Limacina helicina off Cape Webuc, 

 and says they are like winged sweet-peas, the shape of the body 

 and colour suggesting the resemblance. Another species, Clione 

 limacina, with long wings and bright red tints, belongs to the shell- 

 less group Gymnosomata. They sometimes appear in such num- 

 bers as to actually discolour the surface of the water. They are 

 said to afford food for the Greenland whale. The pteropods 

 usually come to the surface in the greatest numbers during the 

 night, and can be caught by using a towing-net. 



The land mollusks of Labrador are few and scarce. The slug 

 Agriolimax agrestis is reported by Packard from Strawberry 

 Harbour, together with the little Pupilla hoppii, Vitrina angelica, 

 and Euconulus fulva, variety fabricii. They occur under spruce 

 bark and chips in the damp verdure, and represent the few truly 

 Arctic species found also in southern Greenland. 



