ECHINODEEMATA OF NEW ENGLAND. 7 



tides, the winds and some unknown conditions. Other 

 things being equal, at the mouth of a bay as at Newport 

 the full tide is best for oceanic larvae, or if one is situated 

 near a small bay where floating material is caught during 

 an ebbing tide, about an hour after the tide begins to fall 

 will generally yield the best results. The first hour of the 

 flood iscommonly the poorest time for surface collecting and 

 the last of the ebb generally gives us the larvae of the litto- 

 ral i'auua rather than the oceanic. The best condition of the 

 sea in which to collect surface animals, adult as well as 

 larvae, is during a calm. \Vhen this happens in Narragan- 

 sett Bay at high tide, after a strong south, or southeasterly 

 wind we may, if ever, expect to find a most abundant and 

 varied life captured in our nets. Smooth places on the 

 surface called "slicks" afford good collecting. Night-time 

 during that calm state of the water which commonly takes 

 place between eight and nine o'clock, is one of the best 

 hours for successful surface fishing. The amount of "phos- 

 phorescence" in the water is an indicator of the abundance 

 of surface life. The character of the animal life which 

 causes the glow can- be in a measure made out by the color 

 of the emitted light. 



As most of the larvae which are treated of in these chap- 

 ters are very minute, almost invisible when swimming in 

 the sea, it is often necessary in collecting to drag the net 

 about apparently at random, "skimming" as it is called the 

 surface of the water, and then lightly washing off into the 

 water of the collecting jars the small animals which al- 

 though not seen have been caught on the meshes. An 

 examination of the capture for identification must be made 

 in a more favorable time and place than at night in the 

 boat. The water into which the-animals have been washed 

 from the drag-net is commonly placed in glass dishes over 

 a black background (tile preferred) and allowed to be- 



