now, this should be basic, but I can't see it

why Weierstrass \rho function is homogeneous of degree -2? i.e. p(cz,c\tau) = c^{-2} p(z,\tau).

If I just use the definition of this function as a sum, I don't see how we can take c^-2 outside...

Weierstrass's elliptic functions. Who is Weierstrass's elliptic functions? What is Weierstrass's elliptic functions? Where is Weierstrass's elliptic functions? Definition of Weierstrass's elliptic functions. Meaning of Weierstrass's elliptic function

sure, we have cz and mc\tau there...but n is not multiplied by c.