Sprats Weather Influences ; Sexual Conditions. 83 



There is a notion that if they come thus in preference to the 

 southerly passages " there are bound to be a good lot of fish." 



How far they may ascend the brackish water of the Med- 

 way and Thames, their daily whereabouts, or how long they 

 may remain in the neighbourhood, are always questionable 

 events. It is noticeable though that with S. and S.E. winds 

 the sprats keep to the south side of the Estuary ; but should 

 N. or N.W. breezes arise the fish cross to the north shore. 

 Sharp cold weather though does not seem to have great sway 

 in retarding first arrival of the shoals. But on gloomy days 

 and fog, or during low tides, they seldom swim on the surface ; 

 thus their presence in lower currents may be undetected. 

 Earlier or later in February there is a tendency to a retrograde 

 or seaward movement. The breeding sprats are noticed to 

 congregate somewhere about the outer Kentish flats, and 

 ultimately retire to their spawning grounds outside. 



As to the period of spawning, our observations point to this 

 as commencing about February or beginning of March, and it 

 continues for several months. Among series examined ab 

 different dates as to the condition of the sexual organs, the 

 undermentioned is an abstract. 



About mid- December the large females (say from 5J to 6 

 inches long) had the ovary in what may be termed the 

 " pinky " (=vascular) stage, and in which minute eggs 

 were discernible by the hand-lens. That is in a moderately 

 advanced stage, but by no means ripe. Males of equal length 

 had the milt firm, but not ready for extrusion. On 31st 

 December a series of females, from 4 to 4*9 inches in extreme 

 length, had the ovaries only slightly developed, the shortest of 

 the fish still less so. On 2nd and 5th January, series ranging 

 from 3f to 5| inches long showed different stages of advance- 

 ment. The smaller ones possessed quite undeveloped roe ; the 

 larger ones only were assuming the " pinky " condition in 

 which minute eggs of varied sizes lay disseminated in the 

 vascular ovarian substance. A 6-inch male had the milt full 

 though not ripe. Other sets examined on the 12th and 19th 



