REPORT OF THE COMMISSIONER OF FISHERIES. 33 
FisHes DistrIBUTED AND STAGE IN WHIcH PLANTED. 
Species. Fry. | "eer | adult. | Total. 
ibanmemiantnblacic basse. s-t6 ccna tempest omen eee as bch Sar | e's afeiafairtat Ro Pde Bae oer Cee 5, 332 
SPUN UME eps Se ae eee Ase ate peas 4, 500 TANG PSE See aes 5, 219 
“Syl. Sips Oa Ta be hls 6 FREE oT E EA TOET ET SE AN ORC erat aes) Pen aes 54, 723 419 55, 142 
DT) TEL See Se Sea on de otee SOISE Seis Je cee eee Bee GG CEe f Seueen so ae 5, 335 4 5, 339 
Petrie tists Soe eee eee oe tae seine Gere telare aninicin ane eciaisisins sare 9, 911, 250 Daou Meee seas ae 9, 935, 600 
aN 8 ta robes cae eg fy ES. oA). ce crsa sh Stet thd xe greats cakes 2,657 144 2) 301 
PMUSSOY PAU C RODS See ee See cate oe se cote one e a ote saa seal ctaroen Be OUO fois siesta ic wal ae picbio nae 83, 000 
TOLLS apa Neat aoe cee INS eras BS RRA 9,998,750 | 93,116 567 | 10, 092, 433 
ARTIFICIAL PROPAGATION OF FRESH-WATER MUSSELS. 
The propagation of fresh-water mussels is pursued in connection 
with the operations of the fisheries biological station at Fairport, 
Iowa, thietly through field parties at various places in the Mississippi 
Basin. The object of this work is the increase of the mussels whose 
shells are utilized in the extensive pearl-button industry. 
During the year the inoculation of fishes with the larval mussels, 
which is the only known method of propagation, was actively con- 
tinued, and increased efficiency is to be noted. Owing to excep- 
tionally high and prolonged flood stages of the central rivers, it was 
impossible at times to accomplish the best results, and the number of 
larval mussels planted was, therefore, slightly less than in the pre- . 
ceding year, being 331,451,490, compared with over 344,000,000 in 
1915. These belonged to seven species of commercial mussels, as 
shown in the following table. The actual cost of production was 1.55 
cents per thousand, but if allowance is made for overhead charges 
the cost per thousand was 2.35 cents, against 2.7 cents in 1915. In 
connection with this work, 34,772 adult and 265,462 fingerling fish 
were rescued from landlocked ponds in the overflowed lands and 
returned to public waters. The total number of fish handled was 
424.550. 
Musset Propagation, Fiscan YEAR 1916: Pornts or DEposir AND SPECIES OF 
Guocuip1a UsEep FoR INFECTION. 
Mississippi River. Black White 
Wabash River: River: 
Species River: Vin-| Black Newport, Total. 
Fairport, | Lake Pepin, |cennes, Ind.|Rock, Ark.,} Ark., and 
Towa. Minn. and south. | vicinity. 
Black sand-shell (Lampsilis 
MCcHA) SIS ARIA IAAL) DE SDBSESOO SE STEARIC ERED VOT AL EOS: EEL ORL 11, 288, 300 
Butterfly (Plagiola securis)... 415; 8003] n.cqctonct 2 -5¢ 52 essa dances esorsiced Suter 411, 800 827, 600 
Lake Pepin mucket (Lamp- 
SilisVuteola)). 022. se2 e255: PUBL TOM lei be GS 00) Ee oe eM eee es ys ae 595 age 151, 195, 990 
Mucket (Lampsilis ligamen- 
Lee te eS 7804s CU CT, Ses! 3, 553, 500 | 26,711,100 | 63,928, 300 | 167, 236, 400 
CRO Re eee eee TERA AUT a el Rk rm Uk Plt late pil bape mt A 147,000 
Pocketbook (Lampsilis ven- 
CELT) SS SSIS ae ae RT ape COV AGUS Bea Ses 4 Be ee Sen. Sere Eammor ere mr 447, 000 
Yellow sand-shell (Lampsilis 
anodontoides)...........-..- S09) 200; | pate oe SGA Ols ergs ee he wereceets Sac MEA ws etree 309, 200 
Matalss Dee. th 2. oh 85, 671, 790 | 151,175,000 | 3,553, 500 | 26, 711,100 | 64,340, 100 | 331, 451, 490 
e 
