intervale over a period of two to four days, the lampreys die and decom- 

 pose rapidly. 



The number of eggs that a female lays is in proportion to her 

 size at maturity. One produced 236,000.2/ Experiments have proved that 

 if a female lamprey is kept away from suitable spawning sites, she dies 

 without releasing her eggs.-*/ 



Sinking to the bottom of the nests, the heavy, small eggs in 

 from one to two weeks hatch into a toothless, eyeless larval form, called 

 ammocoetes. In the month or so that the larvae remain in the nest they 

 reach a length of about a half inch. The young, still eyeless and tooth- 

 less, move downstream and burrow in the mud or sand along the margin of 

 the stream. The current brings them minute organic matter, their only 

 food. At this non-parasitic stage they are termed "mud-eels," "mud 

 lampreys," or "sand lampreys." (Figure z) 



Figure 2 

 Larval forms of the sea lamprey of the Great Lakes: Upper 

 photograph shows side view of untransf ormed larva about 

 lj-l/2 inches long: center photograph, an early eyeless stage, 

 about 1-3/4 inches long; lower, same as upper photograph, 

 but ventral view showing untransf ormed mouth parts* 



gj Simon Henry Oage, The Lampreys of Hew Tork State — Life History and 

 Economics. Biol. Surv. of the Oswego Elver System, Suppl. to 

 l?th Ann. Kept., Hew Tork Cons. Dept., 192?, pp. 15&-191. 



2/ Status of Sea Lamprey Problem, Michigan Conservation, May 19**8. 

 Vol. XVII, No. 5. PP« 12, 15* 



