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SCIENCE 



[N. S. Vol. XL VI. No. 1182 



what increased in the spring when terrapins 

 appear that were overlooked in the fall. 

 Among these young removed from the egg 

 beds there are 666 which are offspring of ter- 

 rapins reared in captivity. The total number 

 of young produced during the previous year, 

 including those found in the spring, was 2,128 ; 

 of these 50 were offspring of terrapins grown 

 in captivity. It has been known for some 

 time that a female terrapin may lay twice 

 during a single season, but during the past 

 season through the discovery of 12 nests, ave- 

 raging 8 eggs to a nest, in a pen where only 

 four females are confined, it is evident that a 

 female may lay as often as three times during 

 a single season. 



The most gratifying results of the past year 

 are the unusually rapid growth of the young 

 of one year and less of age and the very low 

 mortality. The death rate among the 1915 

 brood during the first year was about 8 per 

 cent., while formerly it occasionally ran as 

 high as 40 per cent. The death rate among 

 the young after the age of one year or more 

 is attained is negligible. 



The observations on the habits of fishes was 

 continued by the director of the station. It 

 is very noteworthy that food fishes generally 

 were unusually scarce in the Beaufort region 

 during the past year. The " gray trout " 

 (Cynoscion regalis) which is normally, with 

 perhaps a single exception, the most important 

 food fish of the locality, was so scarce that the 

 fishery was almost wholly abandoned. The 

 almost total failure of a " run " of the two 

 important fall species, the spot (Leiostomus 

 xanthurus) and the jumping mullet {Mugil 

 cephalus), is equally as noteworthy. 



The pig fish {Orthopristis chrysopterus) 

 was found in spawning condition on the inner 

 shore of Shackelford Banks during May and 

 the early part of Jmie, but the eggs of this 

 species seem to be diiEcult to hatch artificially. 

 Spawn taken in the field by stripping was 

 brought to the laboratory for hatching, but 

 these efforts failed. Then ripe or nearly ripe 

 fish were confined in live cars and tanks. 

 Those in the live cars were stripped when ap- 

 parently very ripe, and those in the tanks were 



allowed to spawn naturally. At no time was 

 fertilization obtained in eggs artificially 

 spawned, but of those spawned naturally, a 

 small percentage was successfully fertilized 

 and cell division ensued, but all died before 

 hatching. These experiments having failed, 

 the eggs, which are semibuoyant in sea water, 

 were taken by means of a tow-net and brought 

 to the laboratory. These too died before hatch- 

 ing. The methods of hatching employed were 

 those which are usually successful with other 

 species. 



The study of the life history of Gambusia 

 was continued chiefly for the purpose of veri- 

 fying observations of previous seasons. In 

 connection with the study of fishes in relation 

 to the mosquito problem, it was found that 

 the common eel (Anguilla rostrata) may, at 

 least under more or less abnormal conditions, 

 be of value as an eradicator of mosquito lar- 

 vae, for small specimens taken from reservoirs 

 receiving the overflow of an artesian well were 

 found to have subsisted chiefly on mosquito 

 larva, which in this instance constituted about 

 the only food available. These eels were not 

 confined in these reservoirs, but had come 

 there through choice by passing from salt 

 water through the overflow from the reser- 

 voirs, a passage which remained open for an 

 exit as well as an entrance. This then indi- 

 cates that the common eel should not be over- 

 looked in the study of fishes in relation to the 

 destruction of the mosquito. Several collect- 

 ing trips to fresh-water ponds and streams in 

 the vicinity of the laboratory yielded the fol- 

 lowing species of fishes which do not seem to 

 have been recorded from this immediate vicin- 

 ity; Ameiurus erebennus Jordan, Ameiurus 

 catus (Linnaeus), Erimyzon suceiia (Lace- 

 pede), Notemigonus crysoleucas (Mitchill), 

 Notropis procne (Cope), Dorosoma cepedia- 

 num (LeSueur), Esox americanus Gmelin, 

 Esox reiiculatus LeSueur, Aphredoderiis say- 

 anus (Gilliams), Centrarchus macropierus 

 (Lacepede), Chcenohryttus gulosus (Cuvier & 

 Valenciennes), Enneacanthus gloriosus (Hol- 

 brook), Lepomis giblosus (Linnaus), Lepomis 

 incisor (Cuvier & Valenciennes), Microp- 

 terus salmoides (Lacepede), Perca flavescens 



