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### pcl_ros nodelets do not exist

I'm working with some of the built-in pcl_ros nodelets. I have a VoxelGrid filter and passthrough filter working fine, but when I try to run the SACSegmentation nodelet as decribed in this tutorial, I get the following error:

[ERROR] [1427820107.811356547]: Failed to load nodelet [/normal_estimation] of type [pcl/NormalEstimation]: According to the loaded plugin descriptions the class pcl/NormalEstimation with base class type nodelet::Nodelet does not exist. Declared types are  depth_image_proc/convert_metric depth_image_proc/disparity depth_image_proc/point_cloud_xyz depth_image_proc/point_cloud_xyzi depth_image_proc/point_cloud_xyzrgb depth_image_proc/register freenect_camera/driver image_proc/crop_decimate image_proc/debayer image_proc/rectify image_rotate/image_rotate image_view/disparity image_view/image nodelet_tutorial_math/Plus openni2_camera/OpenNI2DriverNodelet openni_camera/driver pcl/BAGReader pcl/BoundaryEstimation pcl/CropBox pcl/ExtractIndices pcl/FPFHEstimation pcl/FPFHEstimationOMP pcl/MomentInvariantsEstimation pcl/NodeletDEMUX pcl/NodeletMUX pcl/NormalEstimationOMP pcl/PCDReader pcl/PCDWriter pcl/PassThrough pcl/PointCloudConcatenateDataSynchronizer pcl/PointCloudConcatenateFieldsSynchronizer pcl/ProjectInliers pcl/StatisticalOutlierRemoval pcl/VoxelGrid pointcloud_to_laserscan/pointcloud_to_laserscan_nodelet stereo_image_proc/disparity stereo_image_proc/point_cloud2
[ERROR] [1427820107.860576381]: Failed to load nodelet [/planar_segmentation] of type [pcl/SACSegmentationFromNormals]: According to the loaded plugin descriptions the class pcl/SACSegmentationFromNormals with base class type nodelet::Nodelet does not exist. Declared types are  ...


So some of the nodelets apparently aren't being recognized as nodelets by ROS on my system. They aren't listed in the pcl_nodelets.xml file, which is where I'd expect to see them. But I haven't had all that much experience with nodelets to know whether that's true or if I'm just doing something wrong. So is there anything I need to do to make these nodelets recognized?

Or perhaps they've been removed for some reason with the tutorials still existing? That particular filter isn't documented on the main page, anyway.