310 



JAS. J. SIMPSON — ENTOMOLOGICAL 



Table A. 

 Annual Rainfall in Northern Nigeria {in inches). 





a 



1 

 ■§ 



S 



^ 



M 



i 



3 

 1 



i 



1 



1 





1 



1 



•5 ' 



1906 











34-60 





51-83 







60-39 



61-05 



49-00 





1907 





18-11 



19-86 



25-62 



27-55 





36-68 





37-28 



3716 





54-74 





1908 



23-70 



22-30 

 31-89 



2044 

 29-72 



34-86 



53-77 



17-88 



44-12 



46-46 



55-15 



4S-78 



45-48 



55-46 



58-77 



1909 



23-03 



49-03 



44-26 



43-23 



65-14 



55-77 



60-67 



58-89 



55-80 



65-18 



66-85 



1910 



18-21 



19-53 



33-U 



26-81 



38-67 



38-86 



45-49 



47-98 



53-01 



53-44 



53-80 



51-14 



56-44 



■ 

 Mean 



21-65 



22-96 



23-28 



34-08 



39-77 



43-32 



48-65 



50-07 



51-53 



51-73 



54-03 



55-10 



60-69 



.The above table reveals several important facts, but none more obvious 

 .than the striking difference in the rainfall at the various stations. The maximum 

 rainfall recorded during these five years is 66'85 inches, at Ankpa in 1909, and 

 the minimum is 16"87 inches, at Geidam* in 1910, while the difference between the 

 rainfall at Geidam and Ankpa in 1909 amounts to 45"57 inches, or more than 

 twice the total rainfall at the former station. 



A study of the mean annual rainfall at the various stations shows that there is 

 an almost regular increase from the north southwards. At one end of the scale 

 stand Sokoto, Katagum, Maiduguri and Geidam, in the extreme north, and at 

 the other llorin and Ankpa in the south. 



Table B. 



Monthly Record of Rahifall in Inches for 1909 and 1910. 



1909. 



Station. 



•Jan 



Feb. 



Mar. 



Apr. 



May. 



June. 



July. 



Aug. 



Sept. 



Oct. 1 Nov. 



1 



Dec. 



Geidam 





_ 



_ 



1-05 



1-42 



4-39 



4-79 



7-70 



1-83 



0-08 



_ 



0-02 



Katagum 







— 



— 



o-n 



3-98 



4-05 



4-02 



6-32 



4-17 



0-33 



— 



0-05 



Birnin Kebbi 



— 



— 



— 



2-92 



3-31 



3-35 



2-37 



12-98 



2-34 



0-43 



— 



— 



Sokoto 



— 



. — 



— 



1-55 



1-52 



4-34 



8-72 



10-61 



2-52 



0-40 



. — 



— 



Maiduguri ... 



— 



— 



— 



1-01 



0-75 



4-04 



5-33 



12-06 



8-60 



0-04 



— 



— 



Nafada 



— 



— 



— 



3-59 



1-29 



5-12 



8-66 



10-82 



6-89 



0-90 



— 



— 



Bauchi 







— 



— 



3-99 



2-53 



5-64 



10-76 



11-16 



8-73 



0-42 



. — 







Yola 



— 



— 



0-35 



4-33 



3-90 



10-13 



6-23 



7-56 



8-23 



3-35 



— 



0-18 



Keffi 



— 



1-13 



3-12 



3-39 



4-94 



6-52 



9-10 



14-14 



4-48 



2-20 



— 



— 



Kano 



— 



— 



0-09 



1-75 



8-70 



3-71 



9-01 



17-72 



6-83 



0-77 



— 



0-45 



Ibi 







0-70 



2-7.5 



0-40 



8-48 



5-23 



5-01 



7-57 



8-89 



7-49 



— 



0-78 



Baro 



1-06 



0-80 



3-00 



6-74 



3-49 



6-73 



8-19 



16-92 



6-60 



1-88 



_ 



0-36 



Zaria 



— 



0-36 



__ 



3-56 



5-79 



6-51 



13-11 



16-62 



6-61 



1-74 



— 



1-50 



Zungeru 



0-38 



— 



2-02 



4-66 



3-27 



6-09 



12-88 



11-24 



14-27 



2-78 



— 



1-30 



Kontagora . . . 



— 



. — 



2-51 



6-42 



2-02 



6-22 



13-33 



13-12 



12-87 



3-83 



— 



0-35 



Lokoja 



0-04 



1-32 



5-19 



6-80 



8-20 



6-90 



10-35 



12-13 



10-37 



2-61 



. — 



1-23 



llorin 



0-79 



1-18 



5-30 



7-78 



7-12 



8-32 



9-49 



4-92 



14-12 



4-74 



0-23 



1-19 



Ankpa 



0-39 



— 



3-64 



8-63 



14-02 



7-72 



4-42 



8-12 



10-23 



8-80 



— 



0-88 



* As the records for Geidam are available only for 1909 and 1910, it has been omitted from 

 Table A, but is included in Table B. 



