6-7 EDWARD VII. 



SESSIONAL PAPER No. 22a 



A. 1907 



YIII 



REPORT ON THE MARINE POLYZOA OF CANSO, N.S. 



By George A. Cornish, B.A.. Toronto. 

 Science Master in the Collegiate Institute, Lindsay, Ont. 



Tiie following report embodies the results of about seven weeks' work done at the 

 Marine Biological Station of Canada during July and August, 1902. I collected along 

 the beaches, under wharfs, and on kelp washed on the shore. Some dredging was done 

 in the neighbourhood in from 10-25 fathoms, and one of my best sources was stones, 

 tunicates, sponges, &c., brought up on the trawl of the steamer Active, which went out 

 a few miles daily to fish for cod and haddock in 20 to 25 fathoms. 



My identification depends almost entirely on Hincks' British Marine Polyzoa, as 

 it, the Challenger Keports and VerrilFs Report on Invertebrate Fauna of Vineyard 

 Sound were all the accessible literature at the station on this subject. 



family: iETEID^. 



Aetea truncata (Landsborough). — A colony intermingled with Ohelia commissur- 



alis growing on a mussel shell (Mytilus edulis) was found under a wharf. It is the 

 branched variety, and is exactly like Hincks' illustration, Plate II., fig. 3, except that 



the tubular appendage is absent in every case and that it is considerably more branched. 



family: eucratiid^. 



Gemellaria loricata (Linnaeus). — A beautiful, bushy, white tuft, two and one-half 

 inches high, attached to a stone, was taken by the trawler Active. There is a tinge of 

 brown on the larger branches, but the greater part is pure white; the pits on the wall are 

 extremely small. I have also seen the brown form in about 20 fathoms. In the form 

 and proportion of parts it answers completely to G. willisii, Dawson, as described in 

 Hincks' British Marine Polyzoa, p. 21. 



Scruparia clavata, Hincks. — ^Branches on mussel shells (Mytilus edulis) were 

 found under wharfs. Some in single file, some back to back, are found in the same 

 branch. 



FAMILY : CELLULARIID^. 



Menipea ternata (Ellis and Solander) . — The following are my notes on this species : 

 July 20, a small patch found on an ascidian taken at Canso. I find no trace of an- 

 terior avicularia; lateral avicularia are very distinct, and there is always a large spine 

 on the peristome just inside this avicularium. The operculum varies a good deal in size 

 and shape, and in many is crenate on the free margin, having two or three rounded 

 teeth; it has a thickened border surrounding a deep, flat centre; the tendrils are very 

 long. August 1, speciments were taken from a stone taken by the trawler Active in Che- 

 dabucto Bay, in about 12-20 fathoms. There is no grouping in triplets, but about seven 

 zocBcia occupy each internode; the anterior avicularium is quite distinct on the upper 

 zocEcium of each internode, and also on some others. The lateral avicularia are not so pro- 

 minent as in Hincks' illustrations. The operculum covers the greater part of the orifice, 

 and is marked on the front surface. August 19, a tangle of this species mixed with an 



76 



