December 16, 1898.] 



SCIENCE. 



851 



town or Lanesville. During the latter 

 part of June segmentation stages and early 

 embryos are found. During July embryos 

 of about 1 cm. prevail. Early in August 

 the embryos have reached a length of about 

 2 cm., and during the latter part of August 

 embryos from 3 to 7 cm. in length are most 

 abundant. 



The common skate, Raja erinacea, is abun- 

 dant during June, July and August, and at 

 times fully a bucketful of eggs have been 

 deposited in the ' fish cars ' in a single 

 night. The ripe females may be distin- 

 guished by the color of the lower side of 

 the abdomen, through the thin walls of 

 which the ova may be felt and even seen. 

 Torpedoes with ripe eggs have not been 

 taken. The short-nosed sturgeon, Aeijien- 

 ser brevirostis, is occasionally taken in June, 

 the females bearing ripe eggs. The men- 

 haden, Brevoortia tyrannus, breeds during 

 the month of June, though no young were 

 taken the present year. By the middle of 

 July schools of young fish of about one 

 inch in length are often to be seen. 



Fundulus majalis continues its breeding 

 during June and early July, and its eggs 

 may be artificially fertilized with the sperm 

 of Fundulus heteroclitus. The latter species 

 breeds abundantly from the middle of May 

 until the middle of July, but during the 

 latter part of July and the first of August 

 only a few ripe eggs can be secured. Cyprin- 

 odon variegatus spawns in June. Lucania 

 parva is said to be viviparous. I do not 

 know when it breeds. I am informed that 

 late in July the female pipe-fish bears large 

 ovarian eggs, and the males are still carry- 

 ing embryos in their brood-pouches. Late 

 in August both embryos and pouches have 

 disappeared, and the ovaries contain only 

 immature eggs. 



Two species oiMenidla (gracilis and notata) 

 abound in the neighborhood of the labora- 

 tories. The following has been taken from 

 notes kindly furnished by Dr. C. Judson 



Herrick : On June 5, 1896, Mr. Edwards 

 found Menidia notata spawning at Hyannis 

 in vast numbers. At this time the fish had 

 selected a point in the beach grass above 

 the low-tide level, and at low-tide the eggs 

 were consequently exposed to the sun and 

 dried. Mr. Edwards noted great quantities 

 of spawn and milt, and collected about a 

 quart of the former. During the last days 

 of June and the first ten days of July of 

 the present year the fish were very scarce, 

 though Dr. Herrick found a few ripe females 

 and a very few males. The eggs adhere to 

 each other in thick ropy masses, and to 

 any foreign object with which they come 

 in contact, by means of long threads. Both 

 fertile and unfertile eggs sink to the bottom, 

 and the first cleavage plane appears in 

 about one hour. The eggs may be artifi- 

 cially hatched in jars of runniug water, the 

 period of incubation being ten days. The 

 young fish, which carry a small yolk-sac, 

 are about 6 mm. in length. Fry were 

 skimmed from the surface of the harbor 

 on July 4th, and measured 1.5 cm. in 

 length. On July 9th fry similarly taken 

 measured 2.25 cm. in length. 



The eggs of 31. gracilis resemble those of 

 M. notata, but the species seems to breed 

 later, since many ripe females were taken 

 during the first week in July. The eggs, 

 however, do not undergo artificial fertiliza- 

 tion as readily as those of the first species. 



The mackerel. Scomber scombrus, breeds 

 during the middle and latter part of June, 

 and generally at some distance from the 

 shore. During the early part of the month 

 of August of the present year myriads of 

 young fish, about two inches in length, 

 were found in the southern portion of Mas- 

 sachusetts Bay, showing that the breeding 

 had taken place much nearer the shore than 

 is usual. The butter-fish. Rhombus triacan- 

 thits, breeds during June. The white perch,. 

 Morone americana, breeds in May and June, 

 and the sea-bass, Centropristes striatus, from 



