get cell element from R read.csv object?

Question

In R, I'm trying to get a cell value from a read.csv object. But this is what I get:

a<- tail(sp.csv, n=1L)
a$V1
[1] 5042951
54 Levels: 11054 1156785) 1157947) 1159014) 1166898) 1174855) ... src,trg,sp_len,hops

Where, sp.csv is the read.csv object variable. Even if I try variants like: a$V1[[1]] or a[['V1']][1] what am I doing wrong, any suggestions? What I need is the values from V1 and V2.