SPAT-COLLECTOES. 753 



I have been informed by an old oysterman that pine bushes stuck securely into the sea 

 bottom so as to be submerged in shallow areas have been found very effectual as collectors. 

 In fact, he told me that iu one case which had fallen under his observation an oyster-planter 

 who followed this plan had the satisfaction of seeing his submerged bushes load with spat, 

 much of which afterwards grew to marketable size. Afterwards a productive ridge or bank 

 was the result where the brush palisade had originally acted as a collector. Thick palisades 

 of brush might, be stuck into the bottom near permanent oyster-banks with good results. 

 Doubtless it would be possible to establish banks by this method if, in addition, oyster-shells 

 or stones were strewn on the "bottom along either side of the brush palisade, in order to afford 

 a foundation for the fixation of the first generations of oysters. 



Spat-collectoes. — Lieutenant Winslow, in 1879, used hurdles or nests of half-round tiles, 

 eight to sixteen in number; the results from one placed in the Big Annemessex were very flatter- 

 ing. After it had been immersed twenty-four days 1,506 Oysters had attached themselves. After 

 forty-five days had elapsed 1,334 still remained, and after ninety-three days were past the number 

 still adherent was 539. I have had no such success, but in other parts of the bay, as at Tangier 

 Sound for instance, spat falls in great abundance. I have seen the inner face of one valve of a dead 

 Oyster furnish attachment for over forty spat from one-dghth to three eighths of an inch in 

 diameter. Sponges, pieces of wreck, old shoes, pebbles, iron ore, leather, the external surface of 

 the shell of Modiolaria, branches of trees and logs which have fallen into the water act as collectors. 

 Oysters are sometimes found inside of bottles which have been thrown upon the bottom, the fry 

 having Wandered through the neck and attached itself to the inner surface, growing to the size of 

 two inches in diameter and over. The spat is shaped much like the scallop or Pecten, a form which 

 it often retains until it measures more than two inches in diameter. The primary requisite in 

 collectors is that they shall present clean surfaces while the spawning season is in progress. 

 Small inequalities are probably an advantage, as the very youngest spat is often found in chinks 

 and angles on the shells of the adults. No other organisms should be allowed to grow and cover 

 up or smother the oyster spat. Barnacles, infusoria, moss animals, polyps, and many other 

 organisms are liable to accumulate on the surface of the collectors to the detriment of the young 

 Oysters which have established themselves. Many of these animals, polyps especially, eat the 

 young fry in the free-swimming stage, as shown by Dr. Horst. 



The use of the methods employed abroad for collecting spat has not been tested in the United 

 States upon a scale large enough to enable us to arrive as yet at any very important conclusions. 

 Eoofing slate coated with mortar promises good results; the valves of oyster shells strung upon 

 wire, pine cones, and brush have been used, but in unfavorable places, so as to vitiate to some 

 extent the results which were expected. A coating of cement will not answer; it gets too hard, 

 so that the spat when it is to be removed from the collectors cannot be loosened without injuring 

 its delicate, thin vailves. The coating of lime and sand should be thick enough so as to make a 

 layer of at least an eighth of an inch over the surface of the collector. It should also be allowed 

 to thoroughly " set," as a stone mason would say, after it has been applied so as not to wash off 

 readily. A strong mortar should be mixed for the coating, composed of sharp sand and good 

 lime, in the proportions of about equal parts, and thin enough to dip the slates or tiles into the 

 mixture bodily. If the first eoat is not found to be thick enough a second and third may be 

 applied. The tiles or slates after coating should be allowed to dry for two or three days so as to 

 allow the coating to " set " firmly. 

 48 P 



