263 



par les pecheurs du Niger qui en utilisent la fibre pour la con- 

 fection des cordes et le calfatage de leurs ernbarcations. 



Le " Da des Somonos " produit approximativement en 

 moyenne 700 kilo grammes de semences par tonne de fibres 

 scenes. L'auteur estime que la production moyenne par 

 hectare peut etre evaluee, dans la vallee du Niger, a 700 kilo- 

 grammes de fibres seches par 500 kilogrammes de graines. 



[TRANSLATION.] 



CONTRIBUTION TO THE STUDY OP THE "DA" OF THE 

 SOMONOS (HIBISCUS CANNABINUS). 



Hibiscus cannabimts, L., is an annual of the N.O. Malvaceae, 

 cultivated for its fibre in French West Africa. Its interest as 

 an oil-yielding plant appears less known, and it would seem 

 interesting to give here the results of the investigation made 

 by the Chemical Service of the Jardin colonial of a sample of 

 seeds gathered at Koulikoro (Middle Niger) and sent to France 

 by Governor Clozel. 



Seeds of tetrahedric form. Dimensions : Length 5 to 6 mm, ; 

 width 4 mm.; thickness 2 to 3 mm. Weight of 100 seeds, 

 2*46 grams. Percentage proportion of albumen and seed coat : 

 albumen, 607; seed coat, 39*3. 



The shape of the seeds renders their decortication practically 

 impossible. The analysis carried out by M. P. Ammann was 

 consequently made on the whole seed. 



Water, per cent. ... .. ... 9^64 



Oil, per cent. .. ... ... ... 20-32 



Crude proteins, per cent. ... ... 21-14 



Carbohydrates, per cent. ... ... 15*66 



The oil is a drying oil of a clear yellow colour, which 

 ought to find an opening in the manufacture of paints, 

 varnishes, linoleum, etc. The cake is edible and would form a 

 good cattle food. 



The species of " Da " here referred to is the " Da of the 

 Somonos." This variety is cultivated on the banks of the 

 river by the Niger fishermen, who utilize its fibre for the manu- 

 facture of lines and for caulking their boats. 



The " Da of the Somonos " produces approximately an 

 average of 700 kilograms of seed per ton of dry fibre. The 

 author estimates that the average production per hectare in the 

 valley of the Niger may be taken at 700 kilograms of dry 

 fibre per 500 kilograms of seed. 



