Here's a simple bryce sphere that I multi replicated in bryce. Click on the object then press (alt shift D) to get the multi replicate window to pop up. offset in x and y both to make a spiral. Change the angle or the number to change the appearence. Because I used a 5 degree angle the spheres repeat after 360 degrees (72 spheres was all I really needed). Hopefully you can get thet idea from this image.